Endoscopic inflatable retraction device with additional inflatable chamber

ABSTRACT

An apparatus for retracting an organ inside the body to gain access to an adjacent tissue includes a main chamber which is positionable within the body and inflatable to an expanded condition to retract a body organ. The apparatus includes an inflatable additional chamber which when inflated maintains the main chamber in the expanded condition, and the organ in the retracted condition, notwithstanding release of the main chamber from the inflated condition.

This is a continuation of application Ser. No. 08/106,307 filed on Aug.13, 1993, now abandoned, which is a divisional of application Ser. No.07/794,590, filed on Nov. 19, 1991, now U.S. Pat. No. 5,309,896, whichis a continuation-in-part of application Ser. No. 07/706,781, filed onMay 29, 1991, now abandoned.

BACKGROUND OF THE INVENTION

Laparoscopy dates back to the turn of the 20th Century. Earlylaparoscopic techniques were used primarily for diagnostic purposes toview the internal organs, without the necessity of conventional surgery.Since the 1930s, laparoscopy has been used for sterilization and, morerecently, for the suturing of hernias. U.S. Pat. Nos. 4,919,152 and4,944,443 are concerned with techniques for suturing hernias. Anothervery recent innovation is the use of laparoscopic surgery for removingthe gallbladder.

U.S. patent application Ser. No. 706,781, the application of which thisapplication is a Continuation-in-Part, describes an apparatus and ismethod wherein the abdominal wall is lifted away from the underlyingabdominal organs by an inflatable device which is introducedlaparoscopically and, once in place, inflated to engage and lift anextensive area of the abdominal wall.

Even when such lifting techniques are used, it is still necessary toretract other organs to gain access to the organ or tissue to be treatedor observed. In other procedures, to gain access to the organ or tissueto be treated or observed, it is necessary to separate the organ to betreated from tissue surrounding it. For example, to be able to observethe outer surface the heart, the outer surface of the heart has to beseparated from the pericardium. To obtain the necessary retraction,current laparoscopic procedures use several small retractors insertedthough a plurality of incisions. Because such retractors have arelatively small surface area, they tend to damage and/or cause traumato the retracted organs or tissue. Moreover, the requirement for aplurality of incisions to heal may delay the patient's recovery.

It is known to use a modified Foley catheter to retract organs andtissue with less damage. The modified Foley catheter comprises a small,substantially spherical balloon on the end of a catheter which isinserted through a small incision into the body. After insertion, theballoon is inflated. The modified Foley catheter is used in a similarmanner to a conventional retractor, but the retracted organ or tissue iscontacted by the relatively large surface area of the balloon. Such aretractor reduces damage to retracted organs or tissues, but isinconvenient to use because it has to be kept in place by means of anexternal clamping arrangement, and its relatively large balloon tends toobstruct access to the site to be treated.

SUMMARY OF THE INVENTION

The present invention relates to an inflatable retraction device thatmechanically retracts organs and tissues to provide access to treat orobserve other organs or tissues. More specifically, the invention isconcerned with a retraction device that retracts organs or tissues bymeans of an inflatable chamber. The retraction device is introducedlaparoscopically in a collapsed state into the body and, once in place,inflated to engage an extensive area of the organ or tissue to beretracted, and to gently retract or displace the organ or tissue withoutdamaging it. During laparoscopic treatment and observation procedures, aretraction device according to the invention retains its expandedcondition, and hence its ability to provide retraction, while providingaccess for surgical instruments through itself to the organ or tissuebeing treated or observed, or allowing an organ or tissue to be broughtinside itself for observation or treatment.

In the following description, the word "organ" will be used to mean anorgan or a tissue that is retracted by the retraction device. The word"treat" will be used to mean both treat and observe, and the word"treatment" will be used to mean both treatment and observation. Theword "tissue" or the phrase "tissue to be treated" will both be used tomean the organ or the tissue that is treated through or inside theretraction device.

To provide the large surface area required to retract organs gently, theinflatable retraction device according to the invention is relativelylarge. As a result, the retraction device is normally juxtaposed betweenthe entry through which surgical instruments pass into the body and thetissue to be treated. An inflatable retraction device according to theinvention avoids obstructing the access of surgical instruments to thetissue to be treated by providing one or more apertures in the envelopeof the device. Such apertures allow instruments to pass into and out ofthe interior of the retraction device, or allow the tissue to be treatedto enter the interior of the retraction device for treatment byinstruments passed into the interior of the device. Treatment is thuscarried out working through or inside the retraction device according tothe invention.

In those procedures in which the tissue to be treated enters theinterior of retraction device through an aperture, the material of theretraction device surrounding the aperture may form a seal around thetissue, isolating it from the body outside the retraction device.Treatment of the tissue is carried out inside the retraction device.

According to different aspects of the invention, inflatable retractiondevices according to the invention employ different ways to retain theirability to provide retraction while providing access for surgicalinstruments to the tissue to be treated or observed. An inflatableretraction device according to one aspect of the invention, such aretraction device being designated generally as a Type I retractiondevice, maintains its ability to provide retraction by means of anadditional inflatable chamber, which forms a cage structure inside oroutside the main inflatable chamber. The additional inflatable chamberis normally inflated after the main inflatable chamber of the retractiondevice has been inflated, and the retraction device has produced itsdesired retraction effect. Such an additional inflatable chamber issmaller and less powerful than the main inflatable chamber. Inflatingthe additional chamber alone would not always produce sufficient forceto provide the desired retraction of the organ. However, the inflatedadditional chamber provides enough force to maintain an organ that hasbeen retracted by the more powerful main inflatable chamber in itsretracted position. The additional inflatable chamber is thus able tomaintain the retraction effect of the retraction device after theretraction effect of the main inflatable chamber has been destroyed bypiercing an aperture in the envelope of the main chamber to provideaccess to the tissue to be treated.

The tube used to inflate the main chamber provides primary access forsurgical instruments to the interior of the retraction device. If moreinstruments than can be accommodated by the inflation tube are needed,or if the inflator tube is not conveniently aligned with the tissue tobe treated, instruments can additionally or alternatively be insertedthrough additional incisions. The instruments enter the retractiondevice through additional apertures in the envelope of the main chamber.The apertures are cut in the part of the envelope of the main chamberthat does not form part of the additional inflatable chamber.

In an alternative embodiment of a retraction device according to theinvention, the ability of the retraction device to provide a retractioneffect during the treatment or observation procedure is maintained bykeeping the main chamber of the retraction device in an inflated stateduring the treatment procedure. Such a retraction device, designatedgenerally as a Type II retraction device, does not require an additionalinflation chamber to maintain its retraction effect. An elastomnericwindow is attached to the inside of the retraction device after thedevice has been inflated. The elastomeric window provides a gas-tightseal around instruments passed through it, and around a tissue broughtinto the interior of the retraction device through it.

After the window has been installed, an instrument is passed through thewindow to pierce an aperture in the part of the envelope of theretraction device covered by the window to provide access to the organto be treated. Surgical instruments are passed into the interior of theretraction device, primarily through the main is inflation tube. Theinstruments can pass out of the retraction device to the tissue to betreated through the elastomeric window and the aperture in the envelopeof the main chamber. Alternatively, the tissue to be treated enters theinterior of the retraction device through the aperture and theelastomeric window. The elastomeric window provides a seal around thetissue to be treated enabling the retraction device to be maintained inits inflated state while treatment is carried out.

A Type I or a Type II retraction device according to the invention maybe provided, according to a further aspect of the invention, with tabsattached to the interior surface of the envelope of the device. The tabsare gripped with a suitable gripping tool to adjust the position andorientation of the inflated retraction device relative to the tissue tobe treated. The retraction device may be partially deflated to enableadjustments to be more easily made.

According to a further aspect of the invention, a Type I or a Type IIretraction device may be provided, when in its collapsed state prior toinflation, with markings on its surface to aid proper orientation priorto inflation.

According to a further aspect of the invention, a Type I or a Type IIretraction device according to the invention may further be providedwith a flexible sheath for providing a port to allow surgicalinstruments to pass from outside the body to the main chamber of theretraction device. The interior of the flexible sheath communicates withthe main chamber of the retraction device. The flexible sheath isdeployed after the retraction device has been inflated. According to oneaspect of this invention, a flexible sheath attached to the envelope ofthe retraction device driven outward through the body wall. According toan alternative aspect of this invention, the flexible sheath is driveninward through the body wall to pierce, and to lock into engagementwith, the envelope of the retraction device.

According to a further aspect of the invention, in a retraction deviceaccording to the invention, the part of the envelope of the retractiondevice that is lower-most when the retraction device is deployed in thebody is fitted with an integral tubular suction skirt. The suction skirtis connected to the operating room suction line and allows continuous orintermittent drainage of fluid that collects in the bottom of the cavitycreated by the retraction device during laparoscopic surgery.

An inflatable retraction device according to the method of the inventionis used according to the invention by forming a small opening in thewall of the body and laparoscopically inserting the retraction deviceinto the body in a contracted state. After insertion and orientation,the retraction device is inflated. During the inflation process, therelatively large surface area of the retraction device gently retractsthe organ obstructing access to the tissue to be treated.

After the retraction device has been inflated, surgical instruments arepassed from outside the body into the retraction device. One or moreapertures are created by piercing, and possibly at least partiallyremoving, the envelope of the retraction device adjacent to the tissueto be treated. The one or more apertures in the envelope of theretraction device provide access for the instruments to the tissue to betreated. Treatment is then carried out by working through the one ormore apertures in the retraction device. The apertures may also provideaccess to the interior of the retraction device for surgical instrumentspassed from outside the body. Alternatively, the tissue to be treatedcan enter the main chamber of the retraction device through the one ormore apertures and be treated inside the retraction device.

After the treatment has been completed, the retraction device isdeflated and evacuated prior to its removal from the body in a collapsedstate.

When a inflatable retraction device is used in the abdominal cavity, ainflatable retraction device according to the invention may be usedalone to provide both retraction and lifting of the abdominal wall, orit may be used together with the abdominal lifting devices disclosed inthe application Ser. No. 706,781, of which application this applicationis a Continuation-in-Part, or together with known insufflationtechniques for lifting the abdomen.

The invention is also concerned with methods of using inflatableretraction devices according to the invention in new procedures forsuturing hernias without breaching the peritoneum, anterior resection ofherniated intervertebral discs, resecting the lung, lung lobectomies,and for procedures for observing or treating the heart, the brain, theesophagus, and the prostate.

The various procedures according to the invention involve placing aninflatable retraction device according to the invention inside a part ofthe body, such as the abdomen, the chest, or the skull via a small,limited incision or puncture site. The inflatable retraction device isplaced adjacent to the organ to be displaced. Inflating the retractiondevice retracts the organ and exposes the tissue to be treated.Treatment of the tissue to be treated is then carried out usinginstruments passed into the interior of the retraction device. Thetissue to be treated may remain outside the retraction device, or canenter the retraction device during treatment.

In a procedure according to the invention to repair a hernia by placinga mesh over the site of the hernia, an inflatable retraction device isused to provide retraction and, additionally, to hold the mesh in placeover the site of the Hernia while the mesh is stapled in place.

In a first method of construction according to the invention, a Type IIpolyhedral retraction device is made from suitably shaped pieces of flatplastic film connected together to form a polyhedral main envelopeenclosing the main chamber. Such a construction can be used toapproximate a spherical or spheroidal shape. A main inflation tube isattached to the main envelope such that the interior of the maininflation tube is in communication with the main chamber.

In a first method for constructing a polyhedral Type I retractiondevice, a segmented additional envelope is formed from suitably shapedpieces of flat plastic film. The pieces are shaped to provide therequired cage structure of the additional chamber. The additionalchamber is formed by attaching the periphery of the additional envelopeto the outside or the inside of the main envelope. The part of thesurface of the main envelope that is not covered by the additionalenvelope provides a plurality of windows, which, after the additionalchamber is inflated, may be at least partially removed to provideapertures through which treatment or observation can be carried out. Anadditional inflation tube is attached to the additional envelope suchthat the interior of the additional inflation tube is in communicationwith the additional chamber.

In an alternative method of making an inflatable Type II retractiondevice according to the invention, two curved pieces of plastic film areattached to one another at their peripheries to form a main envelopeenclosing a main chamber. A main inflation tube is attached to the mainenvelope such that the interior of the main inflation tube is incommunication with the main chamber.

In an alternative method for constructing a Type I retraction device, anadditional envelope is formed from two more pieces of curved plasticfilm shaped to form the required cage structure of the additionalchamber. The two pieces of the additional envelope are attached to oneanother either outside or inside the main envelope. The additionalchamber is formed by attaching the periphery of the additional envelopeto the outside or the inside of the main envelope. The part of thesurface of the main envelope that is not covered by the additionalenvelope provides a plurality of windows which, after the additionalchamber is inflated, may be at least partially removed to provideapertures through which treatment or observation can be carried out. Anadditional inflation tube is attached to the additional envelope suchthat the interior of the additional inflation tube is in communicationwith the additional chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a polyhedral Type IA inflatableretraction device according to a first embodiment of the invention;

FIG. 2 is vertical cross section, along the line 2--2 in FIG. 1, of apolyhedral Type IA inflatable retraction device according to a firstembodiment of the invention;

FIG. 3 is horizontal cross sections along the line 3--3 in FIG. 1, of apolyhedral Type IA inflatable retraction device according to a firstembodiment of the invention;

FIG. 4A is a longitudinal cross sectional elevational view of a bodyshowing a packaged collapsed Type IA retraction device according to afirst embodiment of the invention ready for insertion into the abdominalcavity;

FIG. 4B is a longitudinal cross sectional elevational view of a bodyshowing a packaged collapsed Type IA retraction device according to afirst embodiment of the invention after it has been inserted into theabdominal cavity;

FIG. 4C is a longitudinal cross sectional elevational view of a bodyshowing a Type IA retraction device according to a first embodiment ofthe invention during the inflation of its main chamber in the abdominalcavity;

FIG. 4D is a longitudinal cross sectional elevational view of a bodyshowing a Type IA retraction device according to a first embodiment ofthe invention after the additional chamber has been inflated and theinflation pressure has been removed from the main chamber in theabdominal cavity;

FIG. 5 is a longitudinal cross sectional elevational view of a bodyshowing a Type IA retraction device according to a first embodiment ofthe invention used to retract the bowel and lift the liver to expose thegall bladder for observation by an endoscope inserted into the mainchamber of the retraction device through the main inflation tube;

FIG. 6 is a perspective view of a polyhedral Type II inflatableretraction device according to a second embodiment of the inventionshowing an elastomeric window attached to the inner surface of its mainenvelope;

FIG. 7 is a perspective view of an elastomeric window suitable forattaching to the inner surface of the main envelope of a polyhedral TypeII inflatable retraction device according to a second embodiment of theinvention. The elastomeric window includes an electrical element forheating temperature sensitive adhesive applied to one of the surfaces ofthe elastomeric window.

FIG. 8 is a perspective view of the elastomeric window of FIG. 7packaged prior to insertion into the retraction device.

FIG. 9 is a perspective view of the outer surface of the main envelopeof a polyhedral Type II inflatable retraction device according to asecond embodiment of the invention. An elastomeric window has beenattached to the inside of the main envelope and an aperture has been cutin the part of the main envelope covered by the elastomeric window.

FIG. 10A is a longitudinal cross sectional elevational view of a bodyshowing a packaged collapsed Type II retraction device according to asecond embodiment of the invention ready for insertion into theabdominal cavity;

FIG. 10B is a longitudinal cross sectional elevational view of a bodyshowing a packaged collapsed Type II retraction device according to asecond embodiment of the invention after it has been inserted into theabdominal cavity;

FIG. 10C is a longitudinal cross sectional elevational view of a bodyshowing a Type II retraction device according to a second embodiment ofthe invention during the inflation of its main chamber in the abdominalcavity;

FIG. 10D is a longitudinal cross sectional elevational view of a bodyshowing a Type II retraction device according to a second embodiment ofthe invention in its fully inflated condition in the abdominal cavity;

FIG. 11A is a transverse cross sectional elevational view of the abdomenshowing a Type IB retraction device according to a third embodiment ofthe invention during the inflation of its main chamber in the abdominalcavity;

FIG. 11B is a transverse cross sectional elevational view of the abdomenshowing a Type IB retraction device according to a third embodiment ofthe invention in its fully inflated condition in the abdominal cavity;

FIG. 11C is a perspective view of a Type IB retraction device accordingto a third embodiment of the invention showing an alternative form ofadditional cavity having tacked sidewalls.

FIG. 12A is a vertical cross sectional view of a polyhedral inflatableretraction device according to the invention fitted with a firstembodiment of flexible sheath according to the invention installed inthe abdominal cavity with the flexible sheath in its collapsed state.

FIG. 12B is a vertical cross sectional view of a polyhedral inflatableretraction device according to the invention fitted with a firstembodiment of flexible sheath according to the invention installed inthe abdominal cavity showing the flexible sheath being driven throughthe abdominal wall.

FIG. 12C is a vertical cross sectional view of a window of a polyhedralinflatable retraction device according to the invention showing a secondembodiment of a flexible sheath according to the invention.

FIG. 13A is a perspective view of a polyhedral Type IA inflatableretraction devices fitted with a suction skirt according to theinvention;

FIG. 13B is vertical cross section, along the line 2--2 in FIG. 1, of apolyhedral Type IA inflatable retraction device fitted with a suctionskirt according to the invention;

FIG. 14A is a longitudinal cross sectional elevational view of a bodyillustrating the use according to the invention of a retraction deviceaccording to the invention in the abdomen to retract the bowel to gainanterior access to the intravertebral discs, the aorta, or the kidneysfor treatment or observation.

FIG. 14B is a transverse cross sectional elevational view of a bodyillustrating the use according to the invention of a retraction deviceaccording to the invention in the abdomen to retract the bowel to gainanterior access to the intravertebral discs, the aorta, or the kidneysfor treatment or observation.

FIG. 15 is a transverse cross sectional plan view of the chestillustrating the use according to the invention of a retraction deviceaccording to the invention to retract the pericardium from the heart togain access to the surface of the heart for treatment or observation.

FIG. 16A is a transverse cross sectional elevational view of the chestillustrating the use according to the invention of a retraction deviceaccording to the invention to retract the lung away from the pleura togain access to the surface of the lung for treatment or observation.

FIG. 16B is a transverse cross sectional plan view of the chestillustrating the use according to the invention of a retraction deviceaccording to the invention to retract the lung away from the pleura,part of the lung entering the main chamber of the retraction device fortreatment or observation.

FIG. 17 is a longitudinal cross sectional elevational view of the chestillustrating the use according to the invention of a retraction deviceaccording to the invention to retract one lobe of the lung away from therest of the lung to gain access to occlude part of the bronchial treeduring a lobectomy.

FIG. 18 is a longitudinal cross sectional elevational view of theabdomen illustrating the use according to the invention of a retractiondevice according to the invention to retract the liver to gain access tothe gastroesophageal junction prior to sectioning the vagus nerve or totreating gastroesophageal reflux.

FIG. 19 is a longitudinal cross sectional elevational view of the headillustrating the use according to the invention of a retraction deviceaccording to the invention to retract the brain away from the dura materto gain access to the brain for treatment or observation.

FIG. 20A is a transverse cross sectional elevational view of the lowerabdomen illustrating the use according to the invention of a retractiondevice according to the invention between the abdominal wall and theperitoneum to retract the peritoneum to provide laparoscopic access tothe site of a hernia without penetrating the peritoneum. A piece of meshis shown being held in place over the site of the hernia by theretraction device.

FIG. 20B is a transverse cross sectional elevational view of the lowerabdomen showing a retraction device according to the invention in itsfully inflated condition holding a piece of mesh in position on theinside of the peritoneum over the site of the hernia.

FIG. 21 is a perspective view of a retraction device according to theinvention with a piece of mesh attached to the outer surface of the mainenvelope.

FIG. 22A is an exploded perspective view of the components of apolygonal Type IA retraction device illustrating the construction ofsuch a device according to the invention.

FIG. 22B is a plan view of the additional envelope blank of a polygonalType IA retraction device.

FIG. 23A is a perspective view of the additional envelope blank of apolygonal Type IA retraction device showing how a suction skirtaccording to the invention is formed from the additional envelope blank.

FIG. 23B is a plan view of the additional envelope blank of a polygonalType IA retraction device showing how a suction skirt according to theinvention is formed from the additional envelope blank.

FIG. 24A is an exploded perspective view of the components of a flatType IA retraction device illustrating the construction of such a deviceaccording to the invention.

FIG. 24B is a perspective view of the assembled and inflated flat TypeIA retraction device.

FIG. 25A is a perspective view of an inflated triangular prism-shapedType IA retraction device according to the invention.

FIG. 25B is a vertical cross sectional view of an inflated the assembledtriangular prism-shaped Type IA retraction device according to theinvention along the line 25B--25B in FIG. 25A.

FIG. 25C is an exploded perspective view of the components of atriangular prism-shaped Type IA retraction device illustrating theconstruction of such a device according to the invention.

FIG. 25D is a plan view of the additional envelope blank of a triangularprism-shaped Type IA retraction device according to the invention.

FIG. 26 is an exploded perspective view of the components of a polygonalType II retraction device illustrating the construction of such a deviceaccording to the invention.

FIG. 27 is an exploded perspective view of the components of asubstantially hemispherical Type IA retraction device illustrating theconstruction of such device according to the invention.

FIG. 28 is a cross sectional view of a substantially hemispherical TypeIA retraction device.

DETAILED DESCRIPTION OF THE INVENTION

A. Inflatable Retraction Devices

1. Type IA Retraction Device--Basic Embodiment

FIGS. 1, 2, and 3 show perspective, and vertical and horizontal crosssectional views, respectively, of a first embodiment 1 of a retractiondevice according to the invention. This type of retraction device has anadditional inflatable chamber and will be designated as a Type Iretraction device. The Type I retraction device shown in FIGS. 1, 2, and3 with a segmented additional chamber will be designated a Type IAretraction device. The retraction device is shown in its inflatedcondition. The retraction device 1 comprises a main envelope 6 enclosinga main inflatable chamber 11. The main envelope 6 is made of arelatively inelastic and tough film of a plastic such as Mylar®,polyethylene, or polyurethane. The preferred material for the mainenvelope 6 is a polyethylene and nylon composite. The thickness of themain envelope 6 is typically from 0.5 to 5 mils (13 to 130 microns). Theproximal end of a main inflation tube 16 is sealed into the mainenvelope 6. The main inflation tube 16 allows an inflation gas to passinto and out of the main chamber 11. The inflation gas is typically air,nitrogen or carbon dioxide, although other suitable gases may be used.Typical inflation gas pressures are in the range 0.3 to 0.7 pounds persquare inch (psi) (0.21 to 0.48 kPa) , the preferred pressure being 0.5psi (0.35 kPa). The main inflation tube 16 is provided with a port 51 onits distal end, through which endoscopes and/or surgical instruments canbe passed into the main chamber 11. The port 51 allows the inflationpressure of the main chamber 11 to be maintained when surgicalinstruments are passed through the port.

The main envelope 6 of the Type IA retraction device is a polyhedralstructure constructed from two segmented, substantially flat pieces ofplastic film, which gives the retraction device a substantiallypolyhedral shape. Alternatively, two) non-segmented, substantially flatpieces of plastic film can be used to make a relatively flat Type IAretraction device. In a further alternative, the retraction device canbe constructed from curved pieces of plastic film, which gives theretraction device a substantially spherical, spheroidal, or ellipsoidalshape.

The size of retraction devices according to the is invention can rangefrom about 2" (50 mm) wide by about 0.5" (12 mm) high, for use insidethe pericardium, to 10"-14" (250-350 mm) wide by 4"-8" (100-200 mm)high, for use in the abdominal cavity. The size of retraction devicerequired for a given application depends on the application and the sizeof the patient.

In the preferred embodiment, the additional envelope 21 is made from afilm of the same thickness of the same plastic as the main envelope 6.However, in some applications it may be advantageous make the additionalenvelope 21 from a film of a different thickness of the same plastic, orthe same or a different thickness of a different plastic.

The periphery 26 of the additional envelope 21 is attached to thesurface of the main envelope 6. The additional envelope 21 has asegmented shape such that, when its periphery 26 is attached to the mainenvelope 6, and the additional chamber 31 formed between the outside ofthe main envelope 6 and the inside of the additional envelope 21 isinflated, the additional chamber 31 forms a cage structure inside oroutside the main chamber 11, as shown in the figures. When the mainenvelope 6 is a polyhedral structure, the cage structure is preferablyformed on the faces of the polyhedron. The parts of the main envelope 6that do not form part of the wall of the additional chamber 31 provide aplurality of windows 46 that can be punctured to provide access forsurgical instruments into and out of the main chamber 11.

The additional envelope 21 is attached, preferably to the outer surfaceof the main envelope 6, by welding along the periphery 26 of theadditional envelope; alternatively, an adhesive may be applied to theperiphery 26 of the additional envelope 21, and the additional envelope21 brought into contact with the main envelope 6. Other methods thatproduce a flexible, gas-tight seal between the periphery 26 of theadditional envelope 21 and the main envelope 6 may also be used.

One end of an additional inflation tube 41 is sealed into the additionalenvelope 21. The additional inflation tube 41 allows an inflation gas topass into and out of the additional chamber 31. The inflation gas istypically air, nitrogen or carbon dioxide, although other suitable gasesmay be used. Typical inflation gas pressures are in the range 4 to 6 psi(2.8 to 4.1 kPa), the preferred pressure being 5 psi (3.5 kPa). Theinflation gas pressure in the additional chamber is considerably higherthan that in the main chamber to enable the additional chamber to exertsufficient force to keep already retracted organs in their retractedstate despite the much smaller surface area of the additional chamber.The main inflation tube 16 is sealed through the additional envelope 21.

In an embodiment of the Type I retraction device designed for use in aninsufflated body cavity, the main inflation tube 16 and the additionalinflation tube 41 are contained within an inflation tube shield 61,which forms a gas-tight seal with the retraction device. The outer wallof the inflation tube shield 61 forms a gas-tight seal with the trocaror sheath through which it passes into the body cavity. The inflationtube shield 61 can be a separate component. Preferably, an extrusion canprovide the inflation tube shield 61, the main inflation tube 16 and theadditional inflation tube 41 in a unitary structure.

2. Type IA Retraction Device--Alternative Embodiments

The basic embodiment of a Type I retraction device has a singleadditional chamber 31. In alternative embodiments, additional chamber 31is divided into a plurality of sub-chambers (not shown). Thesub-chambers are isolated from one another, so that if one or more ofthem is accidentally punctured while the retraction device is in use,deflation of all of the retraction device can be avoided. Eachsub-chamber can be equipped with its own additional inflation tube.Alternatively, each sub-chamber can be connected to an inflationmanifold (not shown) through a non-return valve (not shown). Thisarrangement requires that each sub-chamber be deliberately punctured todeflate the retraction device in preparation for withdrawing theretraction device from the body at the end of the treatment procedure.

In a further alternative embodiment of the Type IA retraction device,the additional envelope 21 may be attached to the inner surface of themain envelope 6. In this embodiment, the main inflation tube 16 passesthrough the additional chamber and forms a gas-tight seal with theadditional envelope 21 in addition to the main envelope 6.

In a further alternative embodiment of the Type IA retraction device,the additional envelope 21 need not be segmented. The additional chamber31 is formed by attaching the additional envelope 21 to the mainenvelope 6, the line of attachment forming the periphery of the cagestructure of the additional chamber 31. With this arrangement, eachwindow 46 comprises a double thickness of film. This makes it somewhatmore difficult to cut an aperture in a window.

In a further alternative embodiment providing a relatively flat Type IAretraction device shown in FIG. 24B, neither the main envelope 6 nor theadditional envelope 21 are segmented. The additional envelope 21 has anumber of holes cut in it. The additional chamber 31 is formed byattaching the periphery of each hole in the additional envelope 21 tothe main envelope 6.

In a further alternative embodiment, FIGS. 25A, 25B, 25C, and 25D show aType IA retraction device in the shape of a triangular prismparticularly suitable for use in the upper abdomen. In this embodiment,the main envelope 6 and the additional envelope 21 are serratedrectangles, as shown in FIGS. 25C and 25D. The additional envelope hasthree large holes cut in it. The additional chamber 31 is formed byattaching the periphery of each hole in the additional envelope 21 tothe main envelope 6. Opposite ends of the long axis of the rectangle andthe serrations are joined together to form the triangular structure.

All embodiments of the Type IA retraction device may be provided withtabs 56 on the inside the main envelope in accordance with a furtheraspect of the invention, as shown in FIGS. 2 and 3. The tabs 56 may beseparate components attached to the inside of the main envelope 6 bywelding, an adhesive, or some other suitable method. Alternatively, thetabs 56 can be an integral part of the main envelope 6 suitably extendedinto the main chamber 11. Tabs 56 provide points inside the main chamber11 that can be gripped by a suitable gripping tool (not shown) insertedinto main chamber 11 through the main inflation tube 16. The grippingtool allows the inflated retraction device to be manipulated to changeits position so that, for instance, one of its windows can be alignedwith the organ or tissue to be treated or observed. Partially deflatingthe inflated retraction device makes repositioning easier.

3. Type IA Retraction Device--Basic Method of Use

In the following description, the word "organ" will be used to mean anorgan or a tissue that is retracted by the retraction device. The word"treat" will be used to mean both treat and observe, and the word"treatment" will be used to mean both treatment and observation. Theword "tissue" or the phrase "tissue to be treated" will both be used tomean the organ or the tissue that is treated, through or inside theretraction device.

FIGS. 4A through 4D show a cross sectional elevational view of theabdomen A to illustrate the method by which a Type IA retracticon deviceaccording to the invention is inserted into the body and used to retractan organ within the body to gain access to treat a tissue. In the methodillustrated in FIGS. 4A through 4D, the retraction device is insertedinto the abdomen A and is used to retract an organ, the bowel B, to gainaccess to treat a tissue, the gall bladder GB. Similar methods are usedto insert a retraction device according to the invention into otherparts of the body.

Inflatable retraction device 1 is supplied in a collapsed state, asshown in FIG. 4A, in which it is tightly packaged in a configurationthat makes it essentially a linear extension of the inflation tubeshield 61. The retraction device 1 is packed so that when pressure isapplied to the main inflation tube 16, the retraction device 1 deployswithout tangling. Depending on the size of the retraction device 1, thepackaged retraction device will fit through an insertion tube (usually atrocar tube) of between 3 and 20 mm (0.12"-0.8") in diameter, a typicaldiameter being 14 mm (0.55"). The retraction device 1 is retained in itscollapsed state by the sleeve 100 which, in turn, is held together, byone-pull lacing 105. Alternatively, the sleeve 100 can be fitted with atear-off strip (not shown). Pulling on the thread 125 detaches theone-pull lacing 105 or the tear-off strip from the sleeve 100, releasingthe collapsed retraction device 1.

The sleeve 100 can be provided with suitable markings 115 to enable itsorientation to be determined and, if necessary, adjusted, afterinsertion into the body and before inflation.

Prior to starting the procedure, the abdomen A may be lifted to provideadditional working space by gas insufflation, or by one of themechanical devices disclosed in U.S. patent application Ser. No.706,781, of which application this application is aContinuation-in-Part. The insufflated condition of the abdomen A isindicated by the broken line A'.

A small incision is made in the skin of the abdomen A and a trocar (notshown) and trocar tube 120 are inserted into the incision and are driventhrough the wall of the abdomen A. The trocar is withdrawn. A secondsmall incision is made in the skin of the abdomen A and a trocar (notshown) and trocar tube 122 are inserted into tea incision and driventhrough the wall of the abdomen. The trocar is withdrawn and anendoscope 110 is inserted into the trocar tube 122. The second incisionis located so that the endoscope 110 can observe the intended placementsite of the retraction device 1. Alternatively, a small endoscope (notshown), preferably about 2 mm (0.1") in diameter, may be is attached tothe collapsed retraction device so that the location of the retractiondevice inside the abdomen may be determined. With this approach, theendoscope 110 is not used, and the second incision need not be made.

The collapsed retraction device 1 is threaded, with the aid of itsinflation tube shield 61, through the trocar tube 120 into the abdominalcavity AC, as shown in FIG. 4B, and manipulated into its correctposition. The position of collapsed retraction device 1 in the abdominalcavity AC is observed through the endoscope 110: the markings 115 enablethe orientation of retraction device 1 to be determined and adjusted ifnecessary. Alternatively, the position of the collapsed retractiondevice is determined by means of the small endoscope (not shown)attached to the retraction device.

The thread 125 is then pulled to release the sleeve 100 from aroundcollapsed retraction device 1, and the sleeve 101 is withdrawn from theabdominal cavity AC through the trocar tube 120 by means of the thread125.

Once the retraction device 1 is correctly positioned, and released fromits sleeve 100, the main inflation tube 16 is connected to a source ofinflation gas (not shown) and the gas supply is slowly turned on toinflate the main chamber 11. The retraction device 1 slowly expands, asshown in FIG. 4C, progressively displacing the bowel B as its sizeincreases. Throughout the expansion process, the retraction device 1presents a relatively large surface area to the bowel B, and thusdisplaces the bowel B gently, progressively, and without trauma.Although the retraction device 1 retracts the bowel B gently, the mainchamber of the retraction device is capable of exerting the forcenecessary to affect the displacement the bowel B.

Once the retraction device 1 has reached its fully-inflated condition,its position is checked by viewing it through the endoscope 110 and/oran endoscope (not shown) inserted into its main chamber 11 via the maininflation tube 16 and the port 51. The tissue to be treated must becovered by one of the windows 46 of retraction device 1.

If the retraction device 1 is not correctly positioned, the inflationgas pressure is reduced slightly to partially deflate retractiondevice 1. A suitable gripping tool is passed through the port 51 and themain inflation tube 16 into the interior of the retraction device 1, togrip one of the tabs 56 (FIGS. 2 and 3). The gripping tool ismanipulated to correct the positioning error while the position of theretraction device 1 is observed through the endoscope 110 or theendoscope (not shown) in the main chamber 11. Once the error iscorrected, the main chamber 11 of the retraction device 1 is reinflatedby means of the main inflation tube 16.

Once the retraction device 1 is correctly positioned, the additionalinflation tube 41 is connected to a source of inflation gas (not shown)and the additional chamber 31 is inflated to the required pressure, asshown in FIG. 4D. After the additional chamber 31 is fully inflated, thesource of inflation pressure can be removed from the main chamber 11 andthe main inflation tube 16. The port 51 can be removed from the maininflation tube 16 since a gas-tight seal is no longer required aroundinstruments inserted into the main inflation tube 16, the main chamber11 now being at atmospheric pressure.

A cutting instrument 52 is then passed through is the main inflationtube 16 into the main chamber 11 to cut a suitable aperture 54 in thewindow 46 that covers of the tissue to be treated, as shown in FIG. 5.Alternatively, an additional puncture may be made in the abdominal walland a cutting instrument 62 passed through this puncture to cut anaperture 54A in a window 58 to gain access to the main cavity 11, andthence to cut a suitable aperture 54 in the window 46. The aperture 54provides an access to the tissue to be treated; for example, the gallbladder GB. The aperture 54 may simply be a cut in the window 46, or allor part of the window 46 may be removed to provide the aperture 54.Those procedures that are carried out using instruments passed throughthe aperture 54 in the window 46 require that more of the window 46 beremoved than those procedures in which the tissue to be treated ispulled inside the retraction device. When the tissue to be treated istreated inside the retraction device, the periphery of the aperture 54through which the tissue is pulled may form a seal around the tissue andisolate it from the body outside the retraction device.

If the main inflation tube is not conveniently placed relative to thetissue to be treated, or if more surgical instruments than can beaccommodated by the main inflation tube 16 are needed to perform thetreatment, an alternative way of passing instruments into the mainchamber 11 is to make at least one further incision in the body wall,the further incision being made in a location adjacent a further window58 of the retraction device, as shown in FIG. 5. A trocar (not shown)with tube 60 is inserted into the further incision and is driven throughthe body wall to pierce the further window 58. The trocar is withdrawnleaving the trocar tube 60 in place. Instruments, e.g., instrument 62are then inserted into the retraction device as required through thetrocar tube 60 and the further window 58.

FIG. 5 additionally shows the retraction device 1 in place in theabdominal cavity AC in its fully inflated form. The main chamber 11 isnot pressurized; the shape of the retraction device is maintained by theinflated additional chamber 31. In FIG. 5, retraction device 1 wasplaced before inflation such that when the main chamber 11 was inflated,the expansion of the retraction device 1 displaced the bowel B to theright of the drawing and lifted the liver L upwards to expose the tissueto be treated, i.e., the gall bladder GB.

After the treatment is completed, the additional chamber 31 isdisconnected from the source of inflation pressure and the pressure inthe additional chamber 31 is released to collapse the retraction device.Collapsing the retraction device is assisted by connecting theadditional inflation tube 41 to a vacuum line (not shown) to evacuatethe additional chamber 31. Once the retraction device 1 is fullycollapsed, the trocar tube 120 is withdrawn from the abdominal cavity,the retraction device 1 is withdrawn through the small abdominalopening, and the openings in the abdominal wall are closed in the normalway.

4. Type II Retraction Device--Basic Embodiment

FIG. 6 shows an alternative embodiment 201 of a retraction device thatmaintains its shape while allowing treatment to be carried out workingthrough or inside it. The alternative embodiment lacks the secondinflatable chamber of the Type I embodiment shown in FIGS. 1 through 5,and has only a main envelope 206 enclosing a main chamber 211. Thesingle chamber embodiment of the retraction device will be designated asa Type II retraction device. The main chamber 211 remains inflatedthroughout the treatment process, access to the tissue to be treatedbeing provided by an elastomeric window 261 attached to the mainenvelope 206. The elastomeric window 261 is self-sealing and maintainsinflation pressure in the main chamber 211 by forming a substantiallygas-tight seal around instruments passed through it. The elastomericwindow 261 also forms a substantially gas-tight seal around the tissueto be treated if the tissue to be treated is pulled through theelastomeric window 261 into the main chamber 211 for treatment.

The main envelope 206 is made of a relatively inelastic and tough filmof a plastic such as Mylar®, polyethylene, or polyurethane. Thepreferred material for the main envelope is a polyethylene and nyloncomposite. The thickness of the main envelope 206 is typically from 0.5to 5 mils (13 to 130 microns). The proximal end of a main inflation tube216 is sealed into the main envelope 206. The main inflation tube 216allows an inflation gas to pass into and out of the main chamber 211.The inflation gas is typically air, nitrogen or carbon dioxide, althoughother suitable gases may be used. Typical inflation gas pressures are inthe range 0.3 to 0.7 psi (0.21 to 0.48 kPa), the preferred pressurebeing 0.5 psi (0.35 kPa) . once the main chamber 211 is fully inflated,the inflation gas pressure can be reduced to about 0.3 psi (0.21 kPa).The main inflation tube 216 is provided with a port 251 an its distalend, through which endoscopes and other surgical instruments can bepassed into the main is chamber 211. The port 251 provides a gas-tightseal around instruments passed through it and allows inflation pressureto be maintained in the main chamber 211 with instruments present.

The main envelope 206 of the Type II retraction device shown in FIG. 6is a polyhedral structure constructed from two segmented, substantiallyflat pieces of plastic film, which gives the retraction device asubstantially polyhedral shape. Alternatively, two non-segmentedsubstantially flat pieces of plastic film can be used to make arelatively flat Type II retraction device. In a further alternative, theretraction device can be constructed from curved pieces of plastic film,which gives the retraction device a substantially spherical orspheroidal shape.

The size of Type II retraction devices according to the invention canrange from about 2" (50 mm) wide by about 0.5" (12 mm) high, forinstance for use inside the pericardium, to 10"-14" (250-350 mm) wide by4"-8" (100-200 mm) high, for use in the abdominal cavity. The size ofretraction device required for a given application depends an theapplication and the size of the patient.

The lack of a additional chamber in the retraction device 201 shown inFIG. 6 makes orientation less critical. If the main envelope 206 isconstructed from one or two curved pieces of film, orientation isparticularly uncritical. If the main envelope 206 is a polyhedralstructure having a number of faces, some orientation is required becausethe tissue to be treated must be substantially centered on one of thefaces. The retraction device 201 can be provided with tabs 256 on theinside the main envelope 206. Tabs 256 may be separate componentsattached to the inside of the main envelope 206 by welding, an adhesive,or some other suitable method. Alternatively, tabs 256 can be anintegral part of the main envelope 206 suitably extended into the mainchamber 211. Tabs 256 provide points on the inside of the main chamber211 that can be gripped by a suitable gripping tool (not shown) insertedinto main chamber 211 through the inflation tube 216 and port 251. Thegripping tool allows the inflated retraction device 201 to bemanipulated to change its position so that the desired point on thetissue to be treated can be substantially centered on one of its faces.Partially deflating the inflated retraction device makes repositioningeasier.

The elastomeric window 261 is installed on the inside of the mainenvelope 206 after the retraction device 201 has been placed in the bodyand inflated. The elastomeric window 261 is shown in FIG. 7 andcomprises a flat piece 266 of a film of an elastomeric material such aslatex or silicone rubber about 0.5" to 1.5" (12 to 37 mm) in diameter.The periphery of the elastomeric film 266 is attached by means of asuitable adhesive, such as an acrylic cement or a silicone adhesive toone of the flat faces of a ring 271 having a square or rectangular crosssection. The ring 271 is circular or elliptical in shape and is of aspringy material such as polyethylene or stainless steel, so that willregain its circular or elliptical shape after being compressed acrossone of its diameters to enable it to be passed through the inflationtube 216. The other flat face 276 of the ring 271 is coated with anadhesive. A pressure-sensitive adhesive such as a contact rubberadhesive may be used. In the preferred embodiment a hot-melt adhesive ofthe type used in woodworking glue guns is used. If a hot-melt adhesiveis used, a heating element 281, made of is a suitable resistance wire,such as Nichrome, is inserted into a narrow groove in then face 276 ofthe ring 271 to which the adhesive is applied. Suitable electrical leads291 are connected to the heating element 281.

Before it can be inserted into the retraction device 201, theelastomeric window must be wrapped across one of its diameters to reduceits width so that it can pass through the main inflation tube 216, asshown in FIG. 8. A one-pull lacing arrangement 205, or a sleeve with atear strip (not shown) can be used wrapped elastomeric window 261 isattached to a manipulation rod 286 for insertion into the retractiondevice. Also attached to the manipulation rod is the thread 225 torelease the one-pull lacing 205 or the tear strip (not shown) find, if atemperature-sensitive adhesive is used, the electrical leads 291 for theheating element 281 (FIG. 7).

The wrapped elastomeric window 261 on the end of the manipulating rod286 is passed through the port 251 and the main inflation tube 216 intothe main chamber 211. The lacing 205 or tear-strip is released, whichallows the elastomeric window 261 to resume its circular shape. Theelastomeric window 261 is then manipulated to bring it into contact withthe main envelope 206 such that the elastomeric window 261 covers thetissue to be treated. If a pressure-sensitive adhesive is used, the face276 of the elastomeric window is pushed against the main envelope 206 toaffix the elastomeric window 261 in place. If a hot-melt adhesive isused, the face 276 of the elastomeric window is placed against the mainenvelope 206 and a suitable source of electric current (not shown) isapplied to the electrical leads 291 for the time required to melt theadhesive and affix the elastomeric window 261 to the main envelopoe 206.

Once the elastomeric window 261 is firmly affixed to the main envelope206, the manipulating rod 286 is detached from it and withdrawn from themain chamber 211. A suitable cutting instrument 252 is passed throughthe port 251 and the main inflation tube 216 into the main chamber 211and through the elastomeric window 261, as shown in FIG. 6. Theelastomeric window 261 forms a gas-tight seal around the cuttinginstrument 252, and re-seals itself after the cutting instrument 252 iswithdrawn. The cutting instrument 252 is used to cut an aperture in thepart 296 of the main envelope 206 that is covered by the elastomericwindow 261. The part 296 of the main envelope 206 is shown by shading inFIG. 9. The aperture 254 may simply be a cut in the part 296 of theenvelope 206, or all or part of the part 296 of the envelope 206 may beremoved to provide the aperture 254. Procedures that are carried outusing instruments passed through the elastomeric window 261 requireremoving more of the part 296 of the envelope 206 than procedures inwhich the tissue to be treated enters the retraction device through theaperture 254 and the elastomeric window 261. When the tissue to betreated is treated inside the retraction device 201, the elastomericwindow 261 forms a seal around the tissue and isolates it from the bodyoutside the retraction device. The treatment procedure is then carriedout by inserting instruments through the port 251 and the main inflationtube 216 into the main chamber 211 and either working through theelastomeric window 261 or working on the tissue to be treated inside thecavity 211.

5. Type II Retraction Device--Basic Method of Use

The retraction device 201 is inserted into the abdomen using a proceduresimilar to that used to insert a Type IA retraction device. Inflatableretraction device 201 is supplied in a collapsed state, as shown in FIG.10A, in which it is tightly packaged in a configuration that makes itessentially a linear extension of the main inflation tube 216. Theretraction device 201 is packed so that when inflation pressure isapplied to the main inflation tube 216, retraction device 201 deployswithout tangling. Depending on the size of the retraction device 201,the packaged retraction device will fit through an insertion tube ofbetween 3 and 20 mm (0.12"-0.8") in diameter, a typical diameter being14 mm (0.55"). The retraction device 201 is retained in its collapsedstate by a sleeve 100 which, in turn, is held together by one-pulllacing 105 or a tear strip (not shown).

The sleeve 100 can be provided with suitable markings 115 to enable itsorientation to be determined and, if necessary, adjusted, afterinsertion into the abdomen and before inflation.

Prior to inserting the retraction device, the abdomen A may be lifted toprovide additional working space by gas insufflation, or by one of themechanical devices disclosed in U.S. patent application Ser. No.706,781, of which application this application is aContinuation-in-Part. The insufflated state of the abdomen A isindicated by the broken line A'.

A small incision is made in the skin of the abdomen A and a trocar (notshown) and trocar tube 120 are inserted into the incision and are driventhrough the wall of the abdomen A. The trocar is withdrawn. A secondsmall incision is made in the skin of the abdomen A and a trocar (notshown) and trocar tube 122 are inserted into the incision and driventhrough the wall of the abdomen. The trocar is withdrawn and anendoscope 110 is inserted into the trocar tube 122. The second incisionis located so that the endoscope 110 can observe the intended placementsite of the retraction device 1. Alternatively, a small endoscope (notshown), preferably about 2 mm (0.1") in diameter, may be attached to thecollapsed retraction device so that the location of the retractiondevice inside the abdomen may be determined. With this approach, theendoscope 110 is not used, and the second incision need not be made.

The collapsed retraction device 201 is threaded, with the aid of itsmain inflation tube 216, through the trocar tube 120 into the abdomen A,and manipulated into its correct position. The position of collapsedretraction device 201 is observed through the endoscope 110: themarkings 115 enable the orientation of the retraction device to bedetermined and adjusted if necessary. Alternatively, the position of thecollapsed retraction device is determined by means of the smallendoscope (not shown) attached to the retraction device.

The thread 125 is then pulled to release the sleeve 100 from around thecollapsed retraction device 201, as shown in FIG. 10B, and the sleeve100 is withdrawn from the abdominal cavity AC through the trocar tube120 by means of the thread 125. The main inflation tube 216 is connectedto a source of inflation gas (not shown). The inflation gas pressure isslowly increased to inflate the main chamber 211. The retraction device201 slowly expands, progressively displacing the bowel B as its is sizeincreases, as shown in FIG. 10C. Throughout the expansion process, theretraction device 201 presents a relatively large surface area to thebowel B, and thus displaces the bowel gently, progressively, and withouttrauma. Although the retraction device 201 retracts the bowel B gently,the main chamber of the retraction device 201 is capable of exerting theforce necessary to effect the displacement of the bowel.

Once retraction device 201 has reached its fully-inflated condition, itsposition is checked by viewing it through either the endoscope 110and/or an endoscope (not shown) inserted into the main chamber 211 ofthe retraction device 201 via the port 251 and the main inflation tube216. The tissue to be treated should be in contact with the mainenvelope 206 and lie substantially directly in line with the maininflation tube 216. Further, it the retraction device is a polyhedron,the tissue to be treated should be substantially centered in one of itsfaces. The position of the retraction device 201 can be adjusted bygripping one or more of the tabs 256 with a suitable gripping tool (notshown), as described above. Once the retraction device 201 is correctlypositioned, the elastomeric window 261 may be installed as describedabove. FIG. 10D shows the retraction device 201 in its fully inflatedstate with the elastomeric window 261 installed, and the instrument 252passed through the elastomeric window 261 and the aperture 254 in themain envelope 206 to treat the tissue to be treated, the gall bladder,GB.

After the treatment is completed, the main chamber 211 is disconnectedfrom the source of inflation pressure and the pressure in the mainchamber 211 is released to collapse the retraction device. Collapsingthe retraction device is assisted by connecting the main inflation tube216 to a vacuum line (not shown) to evacuate the main chamber 211. Oncefully collapsed, the retraction device 201 is withdrawn from theabdominal cavity through the opening in the abdominal wall that remainsafter withdrawing the trocar tube 120. The elastomeric window 261 issufficiently flexible to be withdrawn through the opening in theabdominal wall along with the retraction device 201. The openings in theabdominal wall are then closed in the normal way.

6. Type IB Retraction Device

A further embodiment of the invention, which is a variation on the TypeI retraction device, designated Type IB, is shown in FIGS. 11A, 11B, and11C. This variation has the advantage of providing two large, flatwindows, but has the disadvantage that it does not allow any access totissues lying to the side of the retraction device. The retractiondevice 301 shown in FIGS. 11A and 11B is substantially cylindrical inshape. A stack of one or more toroidal chambers forms the additionalchamber 331. The example shown in FIGS. 11A and 11B has 3 toroidalchambers 325, 327 and 329. Alternatively, as shown in FIG. 11C, a singlechamber having sidewalls 333 that are tacked together can be used forthe additional chamber 331. In this alternative embodiment, the tackedsidewalls form an enclosure having a height that is considerably greaterthan its width. In FIGS. 11A, 11B, and 11C, the diaphragms 307 and 309cover the top and bottom, respectively, of the retraction device 301.The diaphragms 307 and 309, together the inner walls of the toroidalchambers 325, 327, and 329, form the main chamber 311.

The main inflation tube 316 is sealed into the main chamber 311 andallows the main chamber to be inflated. The additional inflation tube341 is sealed into the additional chamber 331. If more than one toroidalchamber is used to provide the additional chamber, the toroidal chambersmay be interconnected and a single additional inflation tube 341 used,or each toroidal chamber may be provided with its own additionalinflation tube (not shown). The latter approach prevents the retractiondevice 301 from collapsing completely if one of the toroidal chambers325, 327, or 329 is accidentally punctured, and also allows the heightof the retraction device to be adjusted by selectively inflating thetoroidal chambers 325, 327, or 329.

The Type IB retraction device shown in FIGS. 12 and 13 is constructedfrom similar materials to the Type IA retraction device, and may befitted with tabs 356, similar to tabs 56 in the Type IA retractiondevice, to enable it to be properly positioned after inflation. Asimilar procedure is used to deploy the Type IB retraction device in thebody as is used to deploy the Type IA retraction device, and will not bedescribed in detail. A similar inflation procedure is used, except thatthe additional chamber may be inflated at least partially at the sametime as the first cavity is inflated. The Type IB retraction devicedepends more for its shape on the additional chamber than the Type IAretraction device. Hence, at least partial inflation of the additionalchamber is necessary to enable the retraction device to displace organsto the side of the retraction device. Inflation pressures similar tothose used for the Type IA retraction device are used.

Treatment procedures using the Type IB retraction device are similar tothose using the Type IA retraction device, except that the Type IBretraction device does not provide access to tissues to the side of thedevice. The diaphragms 307 and 309 are analogous to the windows 46(FIG. 1) of the Type IA retraction device. Either or both of the windowsprovided by the diaphragms 307 and 309 may be pierced to provideapertures though which treatment may be carried out, or through whichthe tissue to be treated may be brought into the retraction device fortreatment, or through which instruments may be passed into and out ofthe main chamber 311.

7. Flexible Sheaths

A further aspect of the invention is the provision in a retractiondevice according to the invention, of one or more flexible sheaths tointerconnect the main chamber of the retraction device and the outsideof the body into which the retraction device is inserted. The flexiblesheath provides a tract through the body wall that allows additionalsurgical instruments or endoscopes to be introduced into the mainchamber of the retraction device, and/or allows tissue and the like tobe removed. In one embodiment of this aspect of the invention, theflexible sheath is attached to a window of a Type I retraction device orto the main envelope of a Type II retraction device. FIG. 12A shows aflexible sheath according to the invention attached to a window 46 of aType IA retraction device 1, which is shown as an example. A flexiblesheath according to this aspect of the invention can also be used withType IB and Type II retraction devices. The flexible sheath 3 issubstantially cylindrical in shape with a closed distal end 8. Theproximal end 13 of the flexible sheath is attached to the outer surfaceof the window 46. The sidewall 18 of the flexible sheath 3 is foldedconcertina-style when the retraction device is packaged, and remainsfolded after the retraction device has been inflated. After theretraction device 1 has been deployed in the body, as shown in FIG. 12B,a suitable pointed tool 23 is fed into the main chamber 11 to pierce ahole 28 in the part of the window 46 that is covered by the flexiblesheath 3. The pointed tool 23 is pushed through the hole 28 to engagewith the distal end 8 of the flexible sheath 3. The distal end 8 isfirst pressed against the inner surface of the body wall W using thepointed tool 23. The resulting bulge in the skin S on the outside of thebody indicates where the flexible sheath 3 will emerge. A small incision33 is made in the skin S at that point. The flexible sheath 3 is thendriven by the pointed tool 23 through the body wall W to emerge throughthe incision 33.

With a Type I retraction device, the distal end 8 of the flexible sheath3 is then opened to provide access to the main chamber 11. The flexiblesheath does not have to be gas-tight in the manner of conventionaltrocar sheaths, and permits ordinary surgical instruments to be used.

With a Type II retraction device, the flexible sheath is fitted with agas-tight port similar to the part 251 (FIG. 6) before the distal end 8is opened.

The alternative embodiment of a flexible sheath 43 according to theinvention, shown in FIG. 12C, is not initially attached to theretraction device. A Type IA retraction device 1 is shown in FIG. 12C asan example. A flexible sheath according to this aspect of the inventioncan also be used with Type IB and Type II retraction devices. Theflexible sheath 43 comprises a cylindrical piece of flexible plastic 48with a coaxial locking device 53 on its proximal end. The distal end ofthe flexible sheath for a Type II retraction device must be closed by aport (not shown) similar to the port 251 (FIG. 6) so that pressurizationof the main cavity can be maintained after the flexible sheath 43 hasbeen installed.

The flexible sheath 43 is installed after the retraction device 1 hasbeen deployed in the body. A small incision 58 is made in the skin S ofthe body. The flexible sheath 43 is then driven through the body wall Wby a sharp trocar point (not shown). The trocar point pierces a hole 63in the window 46 of the retraction device 1, and pushes the lockingdevice 53 of the flexible sheath 43 through the hole 63 to engage thelocking device 53 with the window 46. When used with a Type IIretraction device, the locking device 53 forms a gas-tight seal with thewindow 46.

8. Suction Skirt

According to a further aspect of the invention, a retraction deviceaccording to the invention may be fitted with a tubular suction skirt onthe part of the retraction device that is lower-most when the retractiondevice is deployed in the body. FIGS. 13A and 13B show, as an example, apolygonal Type IA retraction device of the type used in the abdominalcavity. The suction skirt of this aspect of the invention can be usedwith other type I and type II retraction devices.

Irrigation is of ten used during surgery to clear away bleeding or bloodclots. This fluid collects in the bottom of the cavity in the bodycreated by the is retraction device and needs to be cleared away. Thesuction skirt 12 an the bottom of the retraction device is connected toa suction line and removes such fluid during the treatment procedure,keeping the cavity clear of accumulated fluids. In the example shown,the suction skirt is a tubular appendage attached to the lower-most,extremity of the retraction device. In the retraction device shown inFIGS. 13A and 13B, the suction skirt is formed from part of theadditional envelope 21 around the bottom window 46. The bottom or sidesof the suction skirt is pierced with between six and twelve holes 17. Inthe embodiment shown, the suction skirt is about 1/4" (6.2 mm) indiameter, and the holes 17 are about 1/8" (3.1 mm) in diameter.

The suction skirt is made of the polyethylene-nylon composite that isthe preferred material for the main envelope 6 of the retraction device.This material is sufficiently resilient that a tubular structure madefrom it can retain its open cross section under a low vacuum. One end ofthe suction skirt is closed; the other is connected to a thin-wallpolyethylene tube 22 that runs up the side of the retraction device toexit the body through the same incision as is used for the inflationtubes. If, as is shown in FIGS. 13A and 13B, the retraction device isused in an insufflated body cavity, the suction skirt tube 22 passesinside the inflation tube sheath 61. The distal end of the suction skirttube 22 has attached to it a connector suitable for attaching to anoperating room suction line.

B. Surgical Procedures Using Inflatable Retraction Devices

1. Retracting the Bowel to Provide Anterior Access to the Spine, theAorta, the Kidneys, etc.

The method according to the invention of using a retraction deviceaccording to the invention in a procedure to perform an anteriorresection of a herniated intervertebral disc is illustrated in FIG. 14.A method can be adapted to gain anterior access to the aorta, thekidneys, and other tissues that lie outside the peritoneum. FIG. 14Ashows a longitudinal cross section of the body; and FIG. 14B shows atransverse cross section along the line 14B--14B in FIG. 14A. Anterioraccess to the spine is normally difficult due to the difficulty ofretracting the overlying bowel using conventional laparoscopicretractors. A Type I or a Type II retraction device according to theinvention is used according to the invention to retract the bowel byforming a small incision 420 in the abdominal wall W and inserting atrocar (not shown) with trocar tube 430 into the incision 420 anddriving the trocar into the abdominal cavity AC. The trocar is removedand the retraction device 401 is passed through the trocar tube 430 intothe abdominal cavity AC in its contracted state with the aid of itsinflation tube or inflation tube shield (the inflation tube shield 461of a Type IA retraction device is shown). After insertion andorientation, the main chamber 411 of the retraction device 401 isinflated with a suitable inflation gas passed though inflation tube 416.During the inflation process, the relatively large surface area of themain chamber 411 of the retraction device gently retracts the bowel 431,either upwards or downwards, depending on the position of the disc to betreated. The positioning of the retraction device is checked andadjusted, if necessary, as previously described.

If a Type I retraction device is used, it must be positioned such thatthe disc that it is desired to treat is centered in one of its windows.The additional chamber 431 is inflated, and the inflation gas pressurein the 411 main chamber is released. The inflated additional chambermaintains the shape of the retraction device.

If a Type II device is used, an elastomeric window (not shown) isinstalled, as previously described, on the inside of the main envelopein a position that will provide access to the disc to be treated.

The main envelope 406 of both types of retraction device can then bepierced, and partially removed, if necessary. An incision is made in theperitoneum exposed by the retraction device to gain access to and toresect the disc to be treated.

One or more flexible sheaths may be inserted through the abdominal wallto provide access to the interior of the retraction device for surgicalinstruments. If a Type I retraction device is used, normal surgicalinstruments may be used, and such tools may be freely manipulated in thespace created by the retraction device. Because the main chamber of theretraction device is not under pressure, there is no need to uselaparoscopic instruments through rigid trocar tubes. FIGS. 14A and 14Bshow instrument 452 passed from outside the body through the maininflation tube 416 into the main chamber 411. The instrument 452 passesout of the main chamber 411 through an aperture (not shown) pierced inthe window 446.

Once treatment has been completed, the retraction device is deflated andremoved from the body, and the small incisions in the abdominal wallrepaired, as already described.

2. Retracting the Pericardium

A procedure according to the invention in which a small, oblate versionof a Type I or Type II retraction device according to the invention isused to displace the pericardium 403 from the heart 408 is shown in FIG.15, which shows a transverse cross section of the chest. Displacement ofthe pericardium allows the outer surface 413 of the heart 408 to beobserved, and such procedures as endocardial mapping, ablation,transmyocardial revascularization, and defibrillation to be carried out.These procedures have until now been difficult to do laparoscopicallybecause access to the surface of the heart 408 is obstructed by thepericardium 403.

In the procedure according to the invention, a small puncture 418 ismade in the chest wall 423 and through the puncture 418, a smallincision 428 is made in the pericardium 403. An introducer tube (notshown) is inserted to connect the pericardial cavity 453 to outside thepatient. A retraction device 401 according to the invention is insertedusing its inflation tubes (the main inflation tube 416 is shown) throughthe introducer tube into the pericardial cavity 453 so that it restsbetween the surface 413 of the heart and the pericardium 403. Theretraction device 401 is then released from its packing (not shown), asdescribed above, and its main chamber 411 is inflated. During theinflation process, the main envelope 406 of the retraction device gentlydisplaces the heart 408 from the pericardium 403. The position of theretraction device is checked and, if necessary, adjusted.

If a Type I retraction device is used, it must be positioned such thatthe part of the heart that it is desired to treat is centered in one ofits windows. The additional chamber 433 is then inflated and theinflation pressure removed from the main chamber.

If a Type II device is used, an elastomeric window is installed, aspreviously described, on the inside of the main envelope in a positionthat will provide access to the part of the heart to be treated.

Once the retraction device is in position, the introducer tube (notshown) can be withdrawn and the main inflation tube 416 used as a pathfor endoscopes and instruments to pass in to the main chamber of theretraction device.

3. Retracting the Pleura

FIG. 15 shows an endoscope 433 passed through the main inflation tube416 to observe the outer surface 413 of the heart. FIG. 15 also shows aninstrument probe 438 that has been passed through the chest wall 423 tocontact the surface 413 of the heart. The instrument probe 438 is passedthrough the pericardium 403 and the main chamber 411 of the retractiondevice 401, piercing a first window 443 and a second window 448 of theretraction device. After the treatment is completed, the retractiondevice is withdrawn from the pericardial cavity, as already described,and the small incisions in the pericardium and the chest wall arerepaired.

FIG. 16 shows a further procedure according to the invention in which aretraction device according to the invention is used in the pleuralcavity to retract the lung from the pleura to allow observation andmanipulation. FIG. 16A shows a vertical cross sectional view of thechest and FIG. 16B shows a transverse cross section along the line16B--16B in FIG. 16A. A small, oblate version of a Type I or Type IIretraction device 401 according to the invention is used to displace thelung 402 from the pleura 407 to allow resection of a lobe 412 of thelung 402.

In the procedure, a small incision 417 is made in the chest wall 423and, through the incision 417, a trocar (not shown) is inserted toconnect the pleural cavity 432 to outside the patient. The trocar point(not shown) is removed leaving the trocar tube (not shown) connectingthe pleural cavity 432 to outside the patient. A retraction device 401according to the invention is inserted using its inflation tubes(inflation tube 416 is shown) through the trocar tube into the pleuralcavity, so that it rests between the surface of the lung 402 and thepleura 407. The retraction device 401 is then released from its packing(not shown), as described above, and its main chamber 411 is inflated.During the inflation process the main envelope 406 of the retractiondevice gently displaces the lung 402 from the pleura 407. The positionof the retraction device is checked and, if necessary, adjusted.

If a Type I retraction device is used, it must be positioned such thatthe part of the lung that it is desired to treat is centered in one ofits windows. The additional chamber 431 is then inflated and theinflation pressure removed from the main chamber 411.

If a Type II device is used, an elastomeric window is installed, aspreviously described, on the inside of the main envelope in a positionthat will provide access to the part of the lung to be treated.

Once the retraction device is in position, the trocar tube (not shown)can be withdrawn and the main inflation tube 416 used as a path forendoscopes and instruments to pass to the inside of the retractiondevice.

FIG. 16 shows an endoscope 433 passed through the main inflation tube416 into the main chamber of the retraction device 401. In theembodiment of the retraction device 401 shown, the main inflation tube416 enters the main chamber 411 through a first window 443. Part of asecond window 448 has been removed, as already described, to allow apart 437 of the lung 402 to enter the main chamber 411 of retractiondevice for treatment. A trocar tube 447 passes through the chest wall423 and enters the retraction device by piercing a third window 452, andan instrument 442 is passed through the trocar tube 447 to section partof the lung 437. The part of the window 448 that has not been removedforms a seal around the part 437 of the lung inside the retractiondevice, and prevents sectioned tissue from entering the pleural cavity.After the treatment of the lung is completed, the retraction device iswithdrawn from the pleural cavity, as already described, and the smallincisions in the pleura and the chest wall are repaired.

4. Retracting a Lobe of the Lung

In a further procedure according to the invention, a retraction deviceaccording to the invention is used to retract one lobe of a lung in alobectomy. This is shown in FIG. 17, which shows a longitudinal crosssection of the chest. The lobes of the lung overlay one another: inperforming a lobectomy, access to the hilar portion of the bronchialtree is required so that the branches of the bronchial tree feeding thelobe to be sectioned can be occluded. A Type IA or Type II retractiondevice 401 according to the invention is used to displace the lobe 404away from the rest of the lung 409 to provide access to the bronchialtree 414.

In the procedure, a small incision 419 is made in the chest wall 423,and through the incision 419, a trocar (not shown) is inserted throughthe chest wall 423 and pleura 429. The trocar (not shown) is removed andthe trocar tube is maneuvered to place its distal end between the lobe404 and the rest of the lung 409. A retraction device 401 according tothe invention is inserted using its inflation tubes (inflation tube 416is shown) through the trocar tube into position between the lobe 404 andthe rest of the lung 409. The retraction device 401 is then releasedfrom its packing (not shown), as described above, and its main chamber411 is inflated. During the inflation process, the main envelope 406 ofthe retraction device gently displaces the lobe 404 away from the restof the lung 409. The position of the retraction device is checked and,if necessary, adjusted.

If a Type I retraction device is used, it must be positioned such thatthe part of the bronchial tree that it is desired to occlude is centeredin one of its windows. The additional chamber 431 is then inflated andthe inflation pressure removed from the main chamber.

If a Type II retraction device is used, a elastomeric window (not shown)is applied to the inside of the main chamber 411 in a position such thatthe part of the bronchial tree that it is desired to occlude canaccessed through the elastomeric window.

With both types of retraction device, an aperture is cut in the mainenvelope 406 through which the procedure for occluding a part of thebronchial tree can be carried out using instruments passed into the mainchamber 411 through the inflation tube 416. Additional instruments canbe inserted into the main chamber through flexible sheaths (not shown)and/or, in a Type I retraction device, through apertures pierced inother windows (not shown) of the main envelope 406. After the bronchialtree has been occluded, the retraction device is deflated and withdrawn,as already described, from between the lobe 404 and the rest of the lung409. The procedure for sectioning the lobe is carried out before thesmall incisions in the pleura and the chest wall are repaired.

5. Retracting the Liver to Gain Access to the Gastroesophageal Junction

Another procedure according to the invention is shown in FIG. 18. It isnecessary to gain access to the gastroesophageal junction between thestomach 405 and the esophagus 410 to be able to section the vagus nerve,or to treat gastroesophiageal reflux. The gastroesophageal junction isnormally obscured by the liver 415, which must be retracted provideaccess for treating this area. A Type I or Type II retraction device 401according to the invention is used to displace the liver 415 away fromthe esophagus 410. According to the procedure, a small incision 420 ismade in the abdominal wall 425. A trocar (not shown) and trocar tube 440is inserted through the incision 420 and is driven through the abdominalwall 425 into the abdominal cavity AC and the trocar is removed. Thetrocar tube is maneuvered to place its distal end between the liver 415and the esophagus 410. A retraction device 401 according to theinvention is inserted using its inflation tubes (inflation tube 416 isshown) through the trocar tube into position between the liver 415 andthe esophagus 410. The retraction device 401 is then released from itspacking (not shown), as described above, and its main chamber 411 isinflated. During the inflation process the main envelope 406 of theretraction device gently displaces the liver 415 away from the esophagus410. The position of the retraction device is checked and, if necessary,adjusted.

If a Type I retraction device is used, it must be positioned such thatthe gastroesophageal junction is centered in one of its windows. Theadditional chamber 431 is then inflated and the inflation pressureremoved from the main chamber.

If a Type II retraction device is used, a elastomeric window (not shown)is applied to the inside of the main chamber 411 in a position such thatthe gastroesophageal junction can accessed through the elastomericwindow.

With both types of retraction device, an aperture is cut in the mainenvelope 406 through which the treatment procedure can be carried outusing instruments (e.g., instrument 452) passed into the main chamber411 through at least the inflation tube 416. Additionally oralternatively, instruments can be inserted into the main chamber 411through flexible sheaths (not shown) and/or, in a Type I retractiondevice, through apertures pierced in other windows (not shown) in themain envelope 406. After the treatment procedure has been carried out,the retraction device is deflated and withdrawn, as already described,from between the liver 415 and the esophagus 410, the small incisions inabdominal wall are repaired.

6. Retracting the Dura Mater

Another procedure according to the invention is is shown in FIG. 19,which shows a vertical cross section of the head. To observe and treatthe brain 450, it is necessary to separate the brain from the overlyingdura mater 455. A small, very oblate version of a Type I or Type IIretraction device 401 according to the invention is used in thisprocedure. According to the procedure, a small incision 460 is made inthe skin of the head, and, working through the incision, a small hole465 is drilled in the skull to provide access to the dura mater 455. Anincision 470 is made in the dura mater to expose the surface of thebrain 450. A retraction device 401 according to the invention isinserted using forceps through the incision 460, the hole 465, and theincision 470 into the skull between the surface of the brain 450 and thedura mater 455. The retraction device 401 is then released, as describedabove, from its packing (not shown), and its main chamber 411 isinflated. During the inflation process the main envelope 406 of theretraction device gently displaces the brain 450 away from the duramater 455. The position of the retraction device is checked and, ifnecessary, adjusted.

If a Type I retraction device is used, it must be positioned such thatpart of the brain that it is desired to treat is centered in one of itswindows. The additional chamber (not shown) is then inflated and theinflation pressure removed from the main chamber.

If a Type II retraction device is used, a elastomeric window (not shown)is applied to the inside of the main chamber 411 in a position such thatthe part of the brain that it is desired to treat can be accessedthrough the elastomeric window.

With both types of retraction device, an is aperture is cut in the mainenvelope 406 through which the treatment procedure can be carried out,using instruments passed into the main chamber 411 through the inflationtube 416. Additionally or alternatively, instruments can be insertedinto the main chamber, in a Type I retraction device, through aperturespierced in other windows (465, 470) of the main envelope 406. After thetreatment procedure has been carried out, the retraction device isdeflated and withdrawn, as already described, from between the brain 450and the dura mater 455. Finally, the small incisions in the dura materand the scalp and the hole in the skull are repaired.

7. Hernia Repair

Laparoscopic techniques are already being used to repair hernias, butconventional techniques require that two incisions be made in theperitoneum, the second incision being a relatively large one, and theperitoneum around the second incision be retracted. These unnecessaryincisions delay recovery and provide the opportunity for complications.A, procedure according to the invention enables hernia repair to becarried out without having to breach the peritoneum. FIG. 20A shows avertical cross section of the lower abdomen. A flat, substantiallyelliptical or rectangular Type IA or Type II retraction device 501according to the invention is used to retract the peritoneum 502 awayfrom the abdominal wall 517. In the procedure according to theinvention, a small incision 522 is made in the abdominal wall 517 nearthe umbilicus 507, and the layers of tissue are cut through as far asthe peritoneum. A retraction device 501 according to the invention isinserted using forceps through the incision 522 into position betweenthe abdominal wall 517 and the peritoneum 502. The retraction device 501is then released, as described above, from its packing (not shown), andits main chamber 511 is inflated. During the inflation process the mainenvelope 506 of the retraction device spreads inferiorly towards theinguinal area, and gently displaces the peritoneum 502 back from theabdominal wall 517. The position of the retraction device is checkedand, if necessary, adjusted.

If a Type I retraction device is used, it must be positioned such thatthe site of the hernia is centered in one of its windows. The additionalchamber 531 is then inflated and the inflation pressure removed from themain chamber.

If a Type II retraction device is used, a elastomeric window (not shown)is applied to the inside of the main chamber 511 in a position such thatthe site of the hernia can be accessed through the elastomeric window.

With both types of retraction device, an aperture is cut in the mainenvelope 506 through which the treatment procedure can be carried outusing instruments passed into the main chamber 511 through the inflationtube 516. Additionally or alternatively, instruments can be insertedinto the main chamber through flexible sheaths (not shown) and/or, in aType I retraction device, through apertures (not shown) pierced in otherwindows of the main envelope 506. After the hernia has been repaired,the retraction device is deflated and withdrawn, as already described,from between the peritoneum 502 and the abdominal wall 517 and the smallincision in the abdominal wall 517 is repaired.

One known technique for repairing a hernia is by suturing or stapling afine mesh over the site of the hernia. The mesh is preferably installedon the abdominal wall outside the peritoneum to prevent the mesh and itssutures or staples from irritating the bowel. Using conventionallaparoscopic techniques to hold the mesh in place while it is cut tosize and stapled in position is a very difficult procedure. In aprocedure according to the invention, a piece of mesh 527 is attached,for instance by a suitable adhesive applied to the perimeter of thepiece of mesh, to substantially cover the window 532 of the retractiondevice 501, as shown in FIG. 21. The window 532 is the window that willcontact the site of the hernia 512 when the retraction device has beendeployed. The retraction device with the mesh is then packaged aspreviously described, and the retraction device is inserted between theperitoneum 502 and the abdominal cavity 517 and inflated, also aspreviously described.

The position of the retraction device 501 is then adjusted, using tabs556 and a suitable gripping tool (not shown) to position themesh-covered window so that the mesh 527 covers the site of the hernia512. Once the retraction device is properly positioned, the additionalchamber 531 is inflated and the inflation pressure removed from the mainchamber. The retraction device 501 holds the mesh 527 in place over thesite of the hernia while the mesh is stapled in place and excess mesh iscut off. Part of the window 532 is cut away, using a suitable toolinserted into the main chamber 511 through the inflation tube 516, toexpose the area of the mesh into which staples will be placed. The meshis stapled to the site of the hernia 512 using staples (not shown)inserted by means of a conventional laparoscopic stapler (not shown).More of the window 532 is then cut away and a suitable laparoscopiccutting tool is inserted into the main chamber 511 to cut the mesharound the stapled area. The excess mesh is removed when the retractiondevice is removed from the body, as previously described.

In a variation on this procedure, a low irritation Dacron® mesh isinstalled on the inside of the peritoneum, the retraction device with apiece of mesh covering one of its windows being inserted into theperitoneal cavity before the retraction device is inflated, as shown inFIG. 20B.

In a variation on both of the above procedures, the mesh is cut to therequired size before it is attached to the window of the retractiondevice. The mesh is attached to the window of the retraction device byone-pull lacing, and the thread for the one-pull lacing is fed throughthe main inflation tube. After the mesh has been correctly positionedand stapled in place, as previously described, the thread is pulled torelease the one-pull lacing, which releases the mesh from the window ofthe retraction device. The retraction device is then withdrawn aspreviously described. This variation does not require the mesh to be cutto size after it has been stapled in place.

C. Methods of Constructing Inflatable Retraction Devices

1. Polygonal Type IA Retraction Device

The construction according to the invention of a polygonal Type IAretraction device is illustrated in FIGS. 22A and 22B. The constructionof a dodecahedral retraction device is illustrated. A dodecahedralretraction device gives a good compromise between approximating aspherical or spheroidal shape, and complexity. Increasing the number offaces makes a shape that is more nearly spherical but is more complex tomake. The additional chamber of a retraction device that is more nearlyspherical provides more retraction force than the additional chamber ofa polyhedral retraction device that is more nearly cubic.

The main envelope and the additional envelope of the retraction deviceare both made of a relatively inelastic and tough film of a plastic suchas Mylar®, polyethylene, or polyurethane. The preferred material is apolyethylene and nylon composite. The thickness of the main envelope istypically from 0.5 to 5 mils (13 to 130 microns). In the preferredembodiment, the additional envelope is made from a film of the samethickness of the same plastic as the main envelope. However, in someapplications it may be advantageous make the additional envelope from afilm of a different thickness of the same plastic, or from a film of thesame or a different thickness of a different plastic.

Two segmented circular main envelope blanks 600 and 601 and twosegmented circular additional envelope blanks 625 and 626 are cut from apiece of film, preferably by die cutting.

The main envelope blank 600, the additional envelope blank 625, and theformation of an envelope half from them will now be described. A similarexplanation applies to the main envelope blank 601, the additionalenvelope blank 626, and the formation of an envelope half from them.

The number of segments in the two main envelope blanks 600 and 601, plus2, determines the number of faces that the polyhedral retraction devicewill have. In the dodecahedral retraction device illustrated, the mainenvelope blank 600 has five segments 605. The width and depth of thesegments 605 determines the shape of the retraction device: wide,shallow segments result is a relatively flat retraction device, whereasnarrow, deep segments result in a relatively tall retraction device.

The number of segments 630 in the additional envelope blank 625 ispreferably equal to the number of segments 605 of the main envelopeblank 600; thus, the additional envelope blank 625 has five segments 630to match the five segments 605 of the main envelope blank 600. The shapeof the segments 630 is substantially the same as that of the segments605, except the parts of each segment 630 indicated by shading and thereference numeral 655 in FIG. 22B are cut away compared with the segment605 in the main envelope blank. When the additional envelope blank 625is assembled with the main envelope blank 600, the cut away areas 655provide the windows 46 (FIG. 1) in the side of the retraction device.Each area 655 will therefore be called a side window area 655. Anotherarea 645 in the center of the additional envelope blank 625 is cut away.When the additional envelope 625 is assembled with the main envelopeblank 600, the cut away area 645 forms the window 46 (FIG. 1) in the topend or the bottom end of the retraction device, and will thus be calledthe end window area 645. The end window area is shown with a circularshape in FIG. 22B; alternatively, it could have a polygonal shape. Theside and end window areas are preferably cut in the same die-cuttingoperation in which the additional envelope is die cut from the plasticfilm.

An envelope half is made by laying the additional envelope blank 625 onthe main envelope blank 600 such that the segments 630 coincide with thesegments 605. The broken line 650 in FIG. 22A indicates the position ofeach side window area 655 when the additional envelope blank 625 iscorrectly positioned on the main envelope bank 600. The periphery ofeach side window area 655 of the additional envelope blank 625 isattached to the main envelope blank 600, preferably by welding.Alternatively, a line of adhesive applied to the periphery of each sidewindow area 655 can be used. The periphery of the end window area 645 inthe additional envelope blank 625 is also attached to the main envelopeblank 600, preferably by welding. Alternatively, a line of adhesiveapplied to the periphery of the end window area 645 can be used.

The envelope half is then given a 3-dimensional form by joining the edge610 of each segment 605 in the main envelope blank 600 to the edge 615of the adjacent segment, and by joining the edge 635 of each segment 630in the additional envelope blank 625 to the edge 640 of the adjacentsegment. The preferred method of joining in this step and the followingsteps involving joining is overlap welding. Alternatively, butt weldingor a line of a suitable adhesive can be used. The envelope half may beformed so that the additional envelope blank 625 is inside or outsidethe main envelope blank 600. In the preferred embodiment, the additionalenvelope blank is inside the main envelope blank.

A second envelope half is made from the main envelope blank 601 and theadditional envelope blank 626, as described above. One of the twoenvelope halves is then inverted relative to the other, and the twoenvelope halves are joined together with the periphery 620 in contactwith the periphery 621 (main envelope) and the periphery 660 in contactwith the periphery 661 (additional envelope). The peripheries of theenvelope blanks on the inside are joined first. In the preferredembodiment, which has the additional envelope outside the main envelope,the envelope halves are joined as follows: the peripheries 620 and 621of the main envelope blanks 600 and 601 are joined first. A small partof the peripheries 620 and 621 of the main envelope blanks is leftunjoined. The main inflation tube 616 is a piece of polyethylene tubingwith an outside diameter in the range of 2.5 to 19.5 mm (0.1" to 0.77")and of suitable length. The distal end of the main inflation tube 616 isfitted with a port 651 that allows surgical instruments to be passedinto the main inflation tube while maintaining inflation pressure in themain chamber of the retraction device. The port 651 also includes afitting (not shown) suitable for connecting the port to a source ofinflation gas (not shown). The proximal end of the main inflation tube616 is inserted into the unjoined part of the peripheries 620 and 621 ofthe additional envelope blanks 600 and 601 and joining the periphery 620to the periphery 621 is completed. Where the peripheries 620 and 621contact the main inflation tube 616, they are joined to the outer wallof the main inflation tube to form a gas-tight seal.

The peripheries 660 and 661 of the outer envelope blanks, i.e., theadditional envelope blanks 625 and 626, are then joined to one anotherand, where they contact the main inflation tube 616, to the outer wallof the main inflation tube to form a gas-tight seal. A small part of theperipheries 660 and 661 of the additional envelope blanks 625 and 626 isleft unjoined. The additional inflation tube 641 is a piece ofpolyethylene tubing with an outside diameter in the range of 2.5 to 5 mm(0.1" to 0.2") and of suitable length. The distal end of the additionalinflation tube 641 is fitted with a is fitting (not shown) suitable forconnecting it to a source of inflation gas (not shown). The proximal endof the additional inflation tube 641 is inserted into the unjoined partof the peripheries 660 and 661 of the additional envelope blanks 625 and626, and joining the periphery 660 to the periphery 661 is completed.Where the peripheries 660 and 661 contact the additional inflation tube641, they are joined to the outer wall of the additional inflation tubeto form a gas-tight seal.

In the alternative embodiment, with the additional envelope inside themain envelope, the peripheries 660 and 661 of the additional envelopeblanks 625 and 626 are joined to one another and to the outer wall ofthe main inflation tube 616. The peripheries 620 and 621 of the mainenvelope blanks 600 and 601 are then joined together, and to the outerwall of the main inflation tube 616 and to the outer wall of theadditional inflation tube 641.

If the retraction device is for use in an insufflated body cavity, themain and additional inflation tubes must be surrounded by an inflationtube shield. The additional envelope blanks for such a retraction deviceare cut to include an inflation tube seal 680 and 681. The inflationtube sheath (not shown) is pushed over the main and additional inflationtubes after they have been sealed into the retraction device and theinflation tube seals are joined to one another, preferably by welding.Alternatively, a suitable adhesive cain be used. Where the inflationtube seals 680 and 681 contact the inflation tube sheath, they arejoined to the outer wall of the inflation tube shield to form agas-tight seal. The above method can be adapted for use if a singleextrusion is used to provide the main and additional inflation tubes andthe inflation tube sheath.

An alternative method of making a polygonal type IA retraction device isthe same as the method just described, except that the additionalenvelope blanks 625 and 626 are cut with the same die as the mainenvelope blanks 600 and 601. A main envelope blank is attached to anadditional envelope blank by welding along the broken lines 650 and 665(FIG. 22A). Alternatively, a main envelope blank can be attached to anadditional envelope blank by a line of a suitable adhesive spread alongthe broken lines 650 and 665. The envelope halves are then formed andattached to one another using the method described above.

The additional chamber of a retraction device in which the additionalenvelope blank and the main envelope blank are cut using the same die issubstantially the same shape as the additional chamber of a retractiondevice in which the additional envelope blank is cut using its own die.The alternative method of construction saves the tooling cost of the dieto cut the additional envelope blank. A retraction device made accordingto this method has a double thickness of film on its windows 46 (FIG.1), which makes it somewhat more difficult to cut apertures in thewindows prior to carrying out the treatment process.

2. Polygonal Type IA Retraction Device with Suction Skirt

The construction according to the invention of a polygonal Type IAretraction device including a suction skirt according to the inventionis illustrated in FIGS. 23A and 23B. A plurality of holes 608,preferably between 6 and 12, are cut around the periphery of the endwindow area 646 of the additional envelope blank 631. Each hole 608 ispreferably about 1/8" (3 mm) in diameter. When the retraction device isdeployed in the body, it must be oriented such that the additionalenvelope blank 631 is lower-most. Additionally, a short radial cut 613is made in the additional envelope blank 631. Preferably, the holes 608and the radial cut 613 are die cut, preferably by the same die used tocut the additional envelope blank 631.

The method of constructing the retraction device is the same as thatdescribed above, except that the step of attaching the periphery of theend window 646 of the additional envelope blank 631 to the main envelopeblank 601 is changed as follows: additional envelope blank 631 isattached to the main envelope blank 601 by welding along a circular lineconcentric with the end window area 646 and displaced radially outwardby about 0.5" (12.5 mm) to lie outside the line of the holes 608. Theweld line is indicated in FIG. 23 by the broken line 618. The part ofthe additional envelope blank 631 forming the periphery of the endwindow area 646 is then displaced radially outwards by about 1/8" (3 mm)and is attached to the main envelope blank 601 by a circular weld,indicated by the broken line 623, inside the line of the holes 608.Displacing the periphery of the end window area radially outward movesthe part of the additional envelope blank 631 between the two weldsindicated by the broken lines 618 and 623 away from the part of the mainenvelope blank that it overlays, and forms a flat tubular structurebetween the two envelope blanks. One end of the tubular structure isclosed by a short radial weld indicated by the broken line 633, close tothe radial cut 613.

Construction of the retraction device is completed as described above.The proximal end of the suction tube 638, which is a piece of thin-wallpolyethylene tubing about 1/4" (6 mm) in outside diameter is insertedinto the open end of the tubular structure provided by the radial cut613. In a retraction device for use in an insufflated body cavity, thesuction tube 638 is sealed into the inflation tube sheath.

The method described above can be adapted to provide a suction skirtaround one of the side windows of a polygonal Type IA retraction device.Such a suction skirt would be useful if the retraction device isoriented with at side window lower-most when in use. The method can alsobe adapted to make a flat retraction device with a suction skirt aroundone or more of its holes or around the junction between its envelopehalves. The method can also be adapted to make a triangular prism-shapedType IA retraction device with a suction skirt around one of its holesor along one or both of the sides of its lower-most face.

3. Relatively Flat Type IA Retraction Device

The construction according to a further aspect of the invention of asimpler, relatively flat Type IA retraction device according to theinvention is illustrated in FIGS. 24A and 24B. The main envelope and theadditional envelope of the retraction device are both made of arelatively inelastic and tough film of a plastic such as Mylar®,polyethylene, or polyurethane. The preferred material is a polyethyleneand nylon composite. The thickness of the main envelope is typicallyfrom 0.5 to 5 mils (13 to 130 microns). In the preferred embodiment, theadditional envelope is made from a film of the same thickness of thesame plastic as the main envelope. However, in some applications it maybe advantageous make the additional envelope from a film of a differentthickness of the same plastic, or from a film of the same or a differentthickness of a different plastic.

Two substantially circular or elliptical main envelope blanks 600 and601, substantially equal in size, and two substantially circular orelliptical additional envelope blanks 625 and 626, substantially thesame size as the main envelope blanks 600 and 601, are cut from a pieceof film, preferably by die cutting. The die cutting process also cutsholes 670 and 671 in the additional envelope blanks 625 and 626respectively. The number, shape, and size of holes 670 and 671 dependson the intended application of the retraction device. When theadditional envelope blanks 625 and 626 are assembled with the mainenvelope blanks 600 and 601 respectively, the holes 670 and 671 form thewindows 646 (FIG. 24B) in the retraction device. Increasing theproportion of the additional envelope removed to form holes 670 and 671increases the window area through which treatment procedures can becarried out, but reduces the ability of the additional cavity of theretraction device to maintain retraction after the main cavity has beenpunctured.

An envelope half is made by laying the additional envelope blank 625 onthe main envelope blank 600. The positions of the periphery of each hole670 when the additional envelope blank 625 is properly positioned on themain envelope bank 600 is indicated by the broken line 650 in FIG. 24A.The periphery of each hole 670 of the additional envelope blank 625 isattached to the main envelope blank 600, preferably by welding.Alternatively, a line of adhesive applied to the periphery of each hole670 can be used. A second envelope half is made from the main envelopeblank 601 and the additional envelope blank 626, using the methoddescribed above.

One of the two envelope halves is then inverted relative to the other,and the two envelope halves are joined together with the periphery 620in contact with the periphery 621 (main envelope) and the periphery 660in contact with the periphery 661 (additional envelope). The envelopehalves may be joined such that the additional envelope blanks 625 and626 are inside or outside the main envelope blanks 600 and 601. In thepreferred embodiment, the additional envelope blanks are inside the mainenvelope blanks. The method of joining the envelope halves is the sameas the method for joining the envelope halves of a polygonal Type IAretraction device, so will not be further described. The completedretraction device is shown in FIG. 24B.

In an alternative embodiment of the relatively flat Type IA retractiondevice, the main inflation tube may be connected to the main chamber bypiercing a hole in one of the windows 646 and attaching the periphery ofthe hole to the outer wall of the inflation tube. This embodiment ismore useful than the basic embodiment, in which the main inflation tubeis connected between the perimeters of the two envelope halves, inprocedures in which the convenient entry point in the body forinstruments lies more or less directly across the short dimension of theretraction device from the tissue to be treated. Examples of suchprocedures are shown in FIGS. 15, 16A, 16B, and 19.

In the alternative embodiment with the additional envelope outside themain envelope, the peripheries 620 and 621 of the main envelope blanksare joined to one another and to the outer wall of the main inflationtube. The peripheries 660 and 661 of the additional envelope blanks arethen joined to one another, and to the outer walls of the main and theadditional inflation tubes.

The flat Type IA retraction device can also be made with its additionalenvelope blanks and its main envelope blanks cut using the same die, asdescribed in connection with the polygonal Type IA retraction device.The main and additional envelope blanks are attached by welding or aline of adhesive along the broken lines 650.

4. Triangular Prism-Shaped Type IA Retraction Device

The triangular prism Type IA retraction device is constructed accordingto the invention from two flat envelope blanks, as shown in FIG. 25C.The main envelope and the additional envelope of the retraction deviceare both made of a relatively inelastic and tough film of a plastic suchas Mylar®, polyethylene, or polyurethane. The preferred material is apolyethylene and nylon composite. The thickness of the main envelope istypically from 0.5 to 5 mils (13 to 130 microns). In the preferredembodiment, the additional envelope is made from a film of the samethickness of the same plastic as the main envelope. However, in someapplications it may be advantageous make the additional envelope from afilm of a different thickness of the same plastic, or from a film of thesame or a different thickness of a different plastic.

A substantially rectangular main envelope blank 700, and a substantiallyrectangular additional envelope blank 725, substantially the same sizeas the main envelope blank 700, are cut from a piece of film, preferablyby die cutting. Each envelope blank 700 and 725 can be regarded as beingdivided lengthwise into three panels. At least the two outer panels haveequal length. Each panel is serrated as shown in FIG. 25C. If the outerpanels are larger than the inner panel, their serrations are truncated,as shown. The serrations are preferably die cut at the same time as theenvelope panels are die cut. The die cutting process also cuts one hole770 in each panel of the additional envelope blank 725, as shown in FIG.25D. Substantially circular holes are shown in FIG. 25D: holes of adifferent shape, or more than one hole per panel can be cut, dependingon the intended application of the retraction device. When theadditional envelope blank 725 is assembled with the main envelope blank700, the holes 770 form the windows 746 (FIG. 25A) in the retractiondevice. Increasing the proportion of the additional envelope removed toform the holes 770 increases the window area through which treatmentprocedures can be carried out, but reduces the ability of the additionalcavity of the retraction device to maintain retraction after the maincavity has been punctured.

Assembly is begun by laying the additional envelope blank 725 on themain envelope blank 700 so that their peripheries overlap. The positionsof the periphery of each hole 770 when the additional envelope blank 725is properly positioned on the main envelope bank 700 is indicated by thebroken line 750 in FIG. 25C. The periphery of each hole 770 of theadditional envelope blank 725 is joined to the main envelope blank 700.The preferred method of joining in this step and the following stepsinvolving joining is overlap welding. Alternatively, a line of adhesiveapplied to the periphery of the pieces being joined, for example, theperiphery of each hole 770, can be used. The periphery 760 of theadditional envelope blank 725 is joined to the periphery 720 of the mainenvelope blank 700 by welding along the broken line 740. A small part ofthe peripheries 720 and 760 is left unjoined.

The additional inflation tube 741 is a piece of polyethylene tubing withan outside diameter in the range of 2.5 to 5 mm (0.1" to 0.2") and ofsuitable length. The distal end of the additional inflation tube 741 isfitted with a fitting (not shown) suitable for connecting it to a sourceof inflation gas (not shown). The proximal end of the additionalinflation tube 741 is inserted into the unjoined part of the periphery720 of the main envelope blank 700 and the periphery 760 of theadditional envelope blank 725, and joining the periphery 720 to theperiphery 760 is completed. Where the peripheries 720 and 760 contactthe additional inflation tube 741, they are joined to the outer wall ofthe additional inflation tube to form a gas-tight seal.

The retraction device is then folded, as shown by the arrows 782 and787, along the boundaries between the panels, i.e., along the lines 710and 715, to bring edge 722 into contact with edge 727 with the mainenvelope blank 700 on the inside. The following parts of the peripheryof the retraction device are then joined: 736 to 741, 737 to 742, 746 to751, 747 to 752, 756 to 761, 757 to 762, 766 to 771, 767 to 772, and 722to 727. A small part of the peripheries 722 and 727 is left unjoined.

The main inflation tube 716 is a piece of polyethylene tubing with anoutside diameter in the range of 2.5 to 19.5 mm (0.1" to 0.77") and ofsuitable length. The distal end of the main inflation tube 716 is fittedwith a port (not shown) that allows surgical instruments to be passedinto the main inflation tube while maintaining inflation pressure in themain chamber of the retraction device. The port also includes a fitting(not shown) suitable for connecting the port to a source of inflationgas (not shown). The proximal end of the main inflation tube 716 isinserted into the unjoined part of the peripheries 722 and 727 andjoining the periphery 722 to the periphery 727 is completed. Where theperipheries 722 and 727 contact the main inflation tube 716, they arejoined to the outer wall of the main inflation tube to form a gas-tightseal.

If the retraction device is for use in an insufflated body cavity, themain and additional inflation tubes must be surrounded by an inflationtube shield. The main and additional envelope blanks for such aretraction device are each cut to include an inflation tube seal 780 and781. The inflation tube sheath (not shown) is pushed over the main andadditional inflation tubes after they have been sealed into theretraction device and the peripheries of the inflation tube seals arejoined to one another. Where the inflation tube seals 780 and 781contact the inflation tube sheath, they are joined to the outer wall ofthe inflation tube shield to form a gas-tight seal. The above method canbe adapted for use if a single extrusion is used to provide the main andadditional inflation tubes and the inflation tube sheath.

The triangular prism-shaped Type IA retraction device can also be madewith its additional envelope blank and its main envelope blank cut usingthe same die, as described in connection with the polygonal Type IAretraction device. The additional envelope blank is attached to the mainenvelope blank by welding or a line of adhesive along the broken lines750.

5. Polygonal Type II Retraction Device

The construction according to the invention of a polygonal Type IIretraction device is illustrated in FIG. 26. The construction of adodecahedral retraction device is illustrated. A dodecahedral retractiondevice gives a good compromise between approximating a spherical orspheroidal shape, and providing windows of a useful size. Increasing thenumber of faces makes a shape that is more nearly spherical but hassmaller faces, which limits the size of elastomeric window that can beused.

The main (and only) envelope of the Type II retraction device is made ofa relatively inelastic and tough film of a plastic such as Mylar®,polyethylene, or polyurethane. The preferred material for the mainenvelope is a polyethylene and nylon composite. The thickness of themain envelope is typically from 0.5 to 5 mils (13 to 130 microns). Toform the main envelope, two segmented circular main envelope blanks 600and 601 are cut from a piece of film, preferably by die cutting. Thenumber of segments 605 in the two main envelope blanks 600 and 601, plus2, determines the number of faces that the polyhedral retraction devicewill have. In the dodecahedral retraction device illustrated, the mainenvelope blanks 600 and 601 each have five segments 605. The width anddepth of the segments 605 determines the shape of the retraction device:wide, shallow segments result is a relatively flat retraction device,whereas narrow, deep segments result in a relatively tall retractiondevice.

An envelope half is formed by joining the edge 610 of each segment 605in the main envelope blank 600 to the edge 615 of the adjacent segment.The preferred method of joining is overlap welding, but butt welding ora suitable adhesive can also be used. A second envelope half is madeusing the main envelope blank 601. One of the two envelope halves isthen inverted relative to the other, and the two envelope halves arejoined together with the periphery 620 in contact with the periphery621. Again, the preferred method of joining is overlap welding, but buttwelding or a suitable adhesive can also be used. A small part of theperipheries 620 and 621 of the two main envelope blanks 600 and 601 isleft unjoined.

The main inflation tube 616 is a piece of polyethylene tubing with anoutside diameter in the range of 2.5 to 19.5 mm (0.1" to 0.77") and ofsuitable length. The distal end of the main inflation tube 616 is fittedwith a port 651 that allows surgical instruments to be passed into themain inflation tube while maintaining inflation pressure in the mainchamber of the retraction device. The proximal end of the main inflationtube 616 is inserted into the unjoined part of the peripheries 620 and621 and joining the periphery 620 to the periphery 621 is completed.Where the peripheries 620 and 621 contact the inflation tube 616, theyare joined to the outer wall of the inflation tube such that a gas-tightmain envelope is formed in contact with the bore of the main inflationtube.

The methods described above for making relatively flat and triangularprism-shaped Type IA retraction devices can easily be adapted to makerelatively flat and triangular prism-shaped Type II retraction devicesrespectively.

6. Curved Type IA and Type II Retraction Devices

Substantially full- or hemi-spherical, spheroidal, or ellipsoidal TypeIA and Type II retraction devices can be made from curved pieces ofplastic film. The construction according to the invention of ahemispherical Type IA retraction device from curved plastic film isillustrated in FIGS. 27 and 28. The method can easily be adapted to makea substantially spherical, spheroidal or ellipsoidal Type IA retractiondevice by interconnecting two envelope halves made according to themethod to be described below using the method for joining envelopehalves described above.

The main envelope 602, the additional envelope 607, and the bottomdiaphragm 647 of the retraction device are all made of a relativelyinelastic and tough film of a plastic such as Mylar®, polyethylene, orpolyurethane. The preferred material is a polyethylene and nyloncomposite. The thickness of the main envelope 602 is typically from 0.5to 5 mils (13 to 130 microns). In the preferred embodiment, theadditional envelope 607 and the bottom diaphragm 647 are made from afilm of the same thickness of the same plastic as the main envelope.However, in some applications it may be advantageous make the additionalenvelope and/or the bottom diaphragm from a film of a differentthickness of the same plastic, or a film of the same or a differentthickness of a different plastic.

A main envelope blank 602, an additional envelope blank 607 and a bottomdiaphragm 647 are cut from a piece of film, preferably by die cutting.The envelope blanks are similar, except that holes 612 are cut in theadditional envelope blank 607. The holes 612 are cut preferably by thesame die that is used to cut the additional envelope blank 607. When theadditional envelope is assembled with the main envelope blank, the holes612 form the windows 646 (FIG. 28). In FIG. 27, holes 612 are shown ashaving a circular shape, but they could have other suitable shapes.

According to one aspect of the method, the main envelope blank 602 andthe additional envelope blank 607 are stretched over the surface of aformer. The surface of the former is the hemispherical, hemispheroidal,hemiellipsoidal, or other shape that it is desired to impart on theenvelope blank. The surface of the former is heated and its temperaturesufficiently high, and the envelope blank remains in contact with thesurface of the former for sufficiently long a time, for the plastic filmof the envelope blank to soften, such that when the envelope blankcools, it adopts the shape of the surface of the former. The surface ofthe former is cooled, the periphery of the envelope blank is trimmed tothe periphery of the surface, and the envelope blank is removed from theformer. An envelope blank can also be curved by blowing the envelopeblank into a suitably-shaped, heated concavity, or by pressing theenvelope blank between suitably-shaped, heated male and female dies.

An envelope half is made by laying the curved additional envelope blank607 on the curved main envelope blank 602. The periphery of each hole612 in the additional envelope blank 607 is attached to the mainenvelope blank 602, preferably by welding. Alternatively, a line ofadhesive applied to the periphery each hole 612 can be used.

In an alternative method, an envelope half is made by laying theadditional envelope blank 607 on the main envelope blank 602. Theperiphery of each hole 612 in the additional envelope blank 607 isattached to the main envelope blank 602, preferably by welding.Alternatively, a line of adhesive applied to the periphery of each hole612 can be used. The resulting flat envelope half is then curved andtrimmed around its periphery using one of the methods described above.

In either of the above methods, the main envelope blank and theadditional envelope blank can cut using the same die, and the secondchamber can be formed by attaching the additional envelope blank to themain envelope blank by welding or applying adhesive along the brokenlines 627. This method produces a retraction device with a double layerof plastic film on the windows 646 (FIG. 28), which makes it somewhatless convenient to use.

A substantially hemispherical retraction device can be made by attachingthe periphery 632 of the main envelope blank 602 to the periphery 637 ofthe additional envelope blank 607, and to the periphery 642 of thebottom diaphragm 647, preferably by welding, as shown in FIG. 28.Alternatively, a line of adhesive applied to the periphery of one orboth the envelope halves and to the periphery 642 of the bottomdiaphragm 647 can be used. A small part of the peripheries 632 and 637is left unjoined. The additional inflation tube 641 is a piece ofpolyethylene tubing with an outside diameter in the range of 2.5 to 5 mm(0.1" to 0.2") and of suitable length. The distal end of the additionalinflation tube 641 is fitted with a fitting (not shown) suitable forconnecting it to a source of inflation gas (not shown). The proximal endof the additional inflation tube 641 is inserted into the unjoined partof the peripheries 632 and 637, and joining the periphery 632 to theperiphery 637 is completed. Where the peripheries 632 and 637 contactthe additional inflation tube 641, they are joined to the outer wall ofthe additional inflation tube to form a gas-tight seal.

A small part of the joint between the periphery 637 of the additionalenvelope blank 607 and the periphery 642 of the bottom diaphragm 647 isalso left unjoined. The main inflation tube 616 is a piece ofpolyethylene tubing with an outside diameter in the range of 2.5 to 19.5mm (0.1" to 0.77") and of suitable length. The distal end of the maininflation tube 616 is fitted with a port 651 that allows surgicalinstruments to be passed into the main inflation tube while maintaininginflation pressure in the main chamber of the retraction device. Theport 651 also includes a fitting (not shown) suitable for connecting theport to a source of inflation gas (not shown). The proximal end of themain inflation tube 616 is inserted into the unjoined part of theperipheries 637 and 642, and joining the periphery 637 of the additionalenvelope blank 607 to the periphery 642 of the bottom diaphragm 647 iscompleted. Where the peripheries 637 and 642 contact the main inflationtube 616, they are joined to the outer wall of the main inflation tubesuch that a gas-tight seal is formed.

The methods described above for making curved envelope halves can alsobe used to make the envelope halves used in constructing a Type IIretraction device.

We claim:
 1. An apparatus for retracting an organ inside the body togain access to an adjacent tissue, the apparatus comprising:a mainchamber having a thin, flexible main envelope, inflating means forselectively inflating the main chamber to an expanded condition while inplace within the body, inflation of the main chamber retracting theorgan to a retracted condition, and inflatable maintaining means,operatively associated with the main chamber, for maintaining the mainchamber in the expanded condition, and the organ in the retractedcondition, notwithstanding release of the inflation of the main chamberfollowing the inflation of the main chamber to the expanded condition,the release of the inflation of the main chamber rendering the mainchamber incapable of maintaining the organ in the retracted condition,the maintaining means having an open structure for providing accesstherethrough to the tissue, wherein the maintaining means comprises:one,and only one, additional chamber, and means for inflating the additionalchamber to an expanded state to maintain the organ in the retractedcondition.
 2. The apparatus of claim 1, wherein the additional chamberis attached to the outside of the main chamber.
 3. The apparatus ofclaim 1, wherein:an additional envelope and part of the main envelopeenclose the additional chamber, the additional envelope covering thepart of the main envelope, and a part of the main envelope not coveredby the additional envelope provides a piercable window.
 4. An apparatusfor retracting an organ inside the body to gain access to an adjacenttissue, the apparatus comprising:a main chamber having a thin, flexiblemain envelope, means for selectively inflating the main chamber to anexpanded condition while in place within the body, inflation of the mainchamber retracting the organ to a retracted condition, and maintainingmeans, operatively associated with the main chamber, for maintaining themain chamber in the expanded condition, and the organ in the retractedcondition, notwithstanding release of the inflation of the main chamberfollowing the inflation of the main chamber to the expanded condition,the release of the inflation of the main chamber rendering the mainchamber incapable of maintaining the organ in the retracted condition,the maintaining means having an open structure for providing access tothe tissue, and including an additional chamber enclosed within the mainchamber.
 5. An apparatus for retracting an organ inside the body to gainaccess to an adjacent tissue, the apparatus comprising:a main chamberhaving a thin, flexible main envelope, means for selectively inflatingthe main chamber to an expanded condition while in place within thebody, inflation of the main chamber retracting the organ to a retractedcondition, maintaining means, operatively associated with the mainchamber, for maintaining the main chamber in the expanded condition, andthe organ in the retracted condition, notwithstanding release of theinflation of the main chamber following the inflation of the mainchamber to the expanded condition, the release of the inflation of themain chamber rendering the main chamber incapable of maintaining theorgan in the retracted condition, the maintaining means having an openstructure for providing access to the tissue, and tab means inside themain chamber for providing a point inside the main chamber that can begripped with a suitable gripping tool to change the position of the atleast partly inflated apparatus.
 6. The apparatus of claim 5, whereinthe tab means is attached to the main envelope.
 7. An apparatus forretracting an organ inside the body to gain access to an adjacenttissue, the apparatus comprising:a main chamber having a thin, flexiblemain envelope, inflating means for selectively inflating the mainchamber to an expanded condition while in place within the body,inflation of the main chamber retracting the organ to a retractedcondition, and inflatable maintaining means, operatively associated withthe main chamber, for maintaining the main chamber in the expandedcondition, and the organ in the retracted condition, notwithstandingrelease of the inflation of the main chamber following the inflation ofthe main chamber to the expanded condition, the release of the inflationof the main chamber rendering the main chamber incapable of maintainingthe organ in the retracted condition, the maintaining means having anopen structure for providing access therethrough to the tissue; and asuction skirt means for providing drainage of the part of the body inwhich the apparatus is deployed, the suction skirt means being attachedto the part of the main envelope that is substantially lower-most whenthe apparatus is deployed in the body.
 8. The apparatus of claim 7,wherein the suction skirt means comprises an elongate tubular structureincluding a side wall having plural holes formed therein, and two ends,at least one of the ends being adapted for connecting to a suction line.